refactor: enhance Overpass API handling with multiple endpoints and improved error reporting

Send a User-Agent to Overpass, overpass-api.de 406s Ruby's default
The Camper POIs plugin died with "plugin exited with status 1": Net::HTTP's bare "Ruby" User-Agent now gets a 406 Not Acceptable from overpass-api.de, any identifying one goes through.
2026-10-09 22:07:45 +02:00 · 2026-10-09 21:51:24 +02:00 · 2026-10-09 21:46:05 +02:00 · 2026-10-08 12:28:05 +02:00 · 2026-09-21 18:08:35 +02:00 · 2026-09-20 16:55:57 +02:00
31 changed files with 5112 additions and 65 deletions
@@ -6,7 +6,14 @@ on:

 jobs:
  check:
-    runs-on: ubuntu-latest
+    # brick-build's job container now points at Gitea's own official
+    # runner image (docker.gitea.com/runner-images:ubuntu-latest, has
+    # Node out of the box) — the earlier opensuse/leap:16.0 image that
+    # failed here on 2026-09-12 (no Node, every step below is a JS-based
+    # Action) got repointed. Pinned to brick specifically again, rather
+    # than the shared ubuntu-latest label "Gitea Runner on Cube" also
+    # answers to.
+    runs-on: brick-build
    steps:
      - uses: actions/checkout@v4

@@ -8,17 +8,25 @@ on:

 jobs:
  renovate:
-    # The native deploy runner (see docs/deployment.adoc) already has
-    # Docker access — Renovate itself is a one-shot batch job, not a
-    # long-running service, so `docker run`, not docker-compose.
-    runs-on: deploy
+    # Same reasoning as check's runs-on in ci.yml: brick-build's job
+    # container now has Node (repointed at Gitea's own official runner
+    # image), which setup-node/npm below need.
+    runs-on: brick-build
    steps:
+      - name: Setup Node
+        uses: actions/setup-node@v4
+        with:
+          node-version: "22"
+
+      - name: Install Renovate
+        run: npm install -g renovate
+
      - name: Run Renovate
-        run: |
-          docker run --rm \
-            -e RENOVATE_PLATFORM=gitea \
-            -e RENOVATE_ENDPOINT="${{ gitea.server_url }}/api/v1/" \
-            -e RENOVATE_TOKEN="${{ secrets.RENOVATE_TOKEN }}" \
-            -e RENOVATE_REPOSITORIES="${{ gitea.repository }}" \
-            -e RENOVATE_ONBOARDING=false \
-            renovate/renovate
+        run: renovate
+        env:
+          RENOVATE_PLATFORM: gitea
+          RENOVATE_ENDPOINT: "${{ gitea.server_url }}/api/v1/"
+          RENOVATE_TOKEN: ${{ secrets.RENOVATE_TOKEN }}
+          RENOVATE_REPOSITORIES: "${{ gitea.repository }}"
+          RENOVATE_ONBOARDING: "false"
+          GITHUB_COM_TOKEN: ${{ secrets.GITHUB_COM_TOKEN }}
@@ -24,6 +24,22 @@ namespace :overpass do
  end
 end

+namespace :hiking do
+  desc "Extract route=hiking relations (name/colour/network/operator, full geometry) from a local " \
+       ".osm.pbf (e.g. one of PmtilesBuilder's own data/geofabrik_cache/*.osm.pbf) and write GeoJSON. " \
+       "Prototype — see lib/maptool/hiking_trails.rb. Usage: rake hiking:trails[input.osm.pbf,out.geojson]"
+  task :trails, %i[pbf out] do |_t, args|
+    %i[pbf out].each { |key| abort("usage: rake hiking:trails[input.osm.pbf,out.geojson]") unless args[key] }
+
+    require_relative "lib/maptool/hiking_trails"
+
+    puts "Extracting hiking routes from #{args[:pbf]}..."
+    geojson = Maptool::HikingTrails.extract(args[:pbf])
+    File.write(args[:out], JSON.generate(geojson))
+    puts "Wrote #{geojson["features"].size} route(s) to #{args[:out]}"
+  end
+end
+
 namespace :gpx do
  desc "Backfill properties.id on Note-category features saved before edit/delete (and its id targeting) existed"
  task :backfill_note_ids do
@@ -12,6 +12,8 @@ independence from connectivity.
 * [x] Shaded relief / DEM layer — hillshade toggle in the sidebar, sourced from public Terrarium tiles online; reads `data/terrain.pmtiles` for offline if one's been generated (see docs/development.adoc), otherwise the toggle is online-only for now
 ** [ ] Terrain slope readout for parking (numeric, not just visual shading)
 * [ ] Contour lines from OSM for hikes and mountain passes
+* [x] Hiking trail overlay — Waymarked Trails raster tiles online (`public/js/hiking_trails.js`), colored per-route by the OSM `colour` tag they already render (the KST/KČT paint-blaze colors in Slovakia/Czechia, plain red elsewhere). Click queries a one-off Overpass `around` search (racing 3 public mirrors) for the route's name/colour/network/operator/distance
+** [x] Offline copy wired in for real, no custom Planetiler profile needed — `Maptool::HikingTrails` (`lib/maptool/hiking_trails.rb`) runs `osmium tags-filter r/route=hiking` + `add-locations-to-ways` + `cat -f opl` against the *same* per-country Geofabrik `.osm.pbf` already downloaded for `offline.pmtiles`, no new download. One `data/hiking_trails/<CODE>.geojson` per country (not one combined file), generated as the last step of every offline build and cached like `geofabrik_cache` (skipped once already newer than its source PBF) — a many-country selection no longer means one giant file, since `GET /api/hiking-trails` lists available countries and the Overlays panel's own checklist only fetches `GET /tiles/hiking_trails/<CODE>.geojson` for whichever ones get ticked. Offline click uses a local `queryRenderedFeatures` hit-test instead of Overpass — instant, no network. See docs/development.adoc
 * [x] Overpass/OSM scripts to extract POIs (drinking water, dump stations, LPG, public toilets, laundromats, shops, springs) — `rake overpass:pois`, see docs/development.adoc; writes a `.geojson` to drop in `data/gpx/` or upload. Also runnable from inside the app itself now, see the import plugins entry below (`plugins/overpass-pois` wraps this same query). Each category now carries a real `POI_ICONS` glyph and color (not p4n2gpx's plain red marker) plus a popup description built from opening_hours/operator/website tags
 * [x] Import plugins: a pluggable way to add more data sources (Park4Night, iOverlander, Freecampsites, ...) without their scrapers necessarily living in this (public) repo — sidebar icon (logged in only) lists whatever's under `plugins/`, "Run for this area" uses the current map viewport as the bbox, no separate area-picker needed. Contract: a `plugin.json` manifest + a script that reads `--south`/`--west`/`--north`/`--east` and prints a GeoJSON `FeatureCollection` to stdout (`lib/maptool/plugins.rb`, `GET /api/plugins`, `POST /api/plugins/:name/run`) — output saved the same way an upload would be. `plugins/overpass-pois` ships as the reference example; a private/ToS-sensitive scraper just drops its own directory in locally and is never `git add`ed
 ** [x] Park4Night — private plugin (`data/plugins/p4n2gpx/`, outside this repo per the "ToS-sensitive scraper" note above); iOverlander/Freecampsites still open, same story
@@ -71,3 +73,12 @@ Deprioritized for now — revisit after the sections above land.
 * [ ] Level gauge from IMU (ESP32/RPi) — camper tilt, wheel-chock leveling calculation
 * [ ] Victron/Home Assistant via MQTT or WebSocket — battery SoC, tank levels, temperatures
 * [ ] Plot GPS track with historical battery/speed data
+
+== Admin / ops tooling
+
+* [ ] Offline build log readability — a failed pmtiles/terrain build currently surfaces as one
+  ~500k-character line; format it for the web UI instead (e.g. per-country/state name + status,
+  not the raw combined stdout/stderr dump)
+* [ ] Expose the build log via an API endpoint, not just embedded in the admin page
+* [ ] Document all API endpoints somewhere and make them easy to browse (status of each) —
+  maybe a status page, login-gated
@@ -15,6 +15,40 @@ require_relative "lib/maptool/plugins"
 require_relative "lib/maptool/pmtiles_builder"

 module Maptool
+  # Only /login, /auth/callback and /logout ever write to session
+  # (oauth_state, user, session.clear) — everything else only ever reads
+  # it, if it touches session at all. That still matters:
+  # Rack::Session::Cookie re-serializes and re-sets the cookie on *every*
+  # response that so much as read session (Rack::Protection's own CSRF
+  # check does, on nearly every request) — reflecting whatever cookie
+  # that particular request happened to arrive with, whether or not
+  # anything changed. A HAR capture caught the actual failure mode this
+  # caused: seconds after a successful login, a background poll fired the
+  # instant the page loads was still carrying the browser's pre-login
+  # cookie (a client-side timing race across the OAuth redirect chain,
+  # not something this server controls), and its own re-issued Set-Cookie
+  # landed *after* the login's, silently overwriting session[:user] with
+  # nothing logged anywhere to explain it.
+  #
+  # A plain Rack middleware, not a Sinatra `before` filter: static assets
+  # (public_folder — every JS/CSS/font/vendor file) are served by
+  # Sinatra's own built-in static-file shortcut, which bypasses route and
+  # filter dispatch entirely but is still wrapped by this, same as every
+  # other response — each one was independently capable of winning the
+  # clobbering race a `before` filter alone left uncovered.
+  class SkipSessionWrite
+    WRITE_PATHS = %w[/login /auth/callback /logout].freeze
+
+    def initialize(app)
+      @app = app
+    end
+
+    def call(env)
+      env["rack.session.options"][:skip] = true unless WRITE_PATHS.include?(env["PATH_INFO"])
+      @app.call(env)
+    end
+  end
+
  class App < Sinatra::Base
    set :public_folder, File.join(__dir__, "public")
    set :views, File.join(__dir__, "views")
@@ -33,6 +67,7 @@ module Maptool
    # don't survive a restart there, which is fine outside production.
    set :sessions, httponly: true, secure: production?, same_site: :lax,
                   secret: ENV.fetch("SESSION_SECRET") { SecureRandom.hex(32) }
+    use SkipSessionWrite

    # Cache-busts /js and /css requests: browsers (and a caching proxy in
    # front of production, see docs/deployment.adoc) hang onto static
@@ -356,6 +391,34 @@ module Maptool
      json ok: true
    end

+    # Generated as a step inside POST /api/offline-tiles/build (see
+    # PmtilesBuilder.extract_hiking_trails) rather than its own separate
+    # build — it's derived from the exact same per-country .osm.pbf cache
+    # offline.pmtiles itself already downloads, so there's nothing of its
+    # own to trigger; DELETE /api/offline-tiles removes it too. One file
+    # per country (not one combined file) so a viewer only ever fetches
+    # the country they actually pick in the Hiking trails overlay's own
+    # checklist (public/js/hiking_trails.js), not every selected country's
+    # trails at once — `countries` lists which ones exist to build that
+    # checklist from.
+    get "/api/hiking-trails" do
+      json countries: PmtilesBuilder.hiking_trails_countries(DATA_DIR)
+    end
+
+    # Fetched client-side only for a country the viewer actually ticks in
+    # the Hiking trails checklist, not on page load. :code is constrained
+    # to exactly what hiking_trails_countries can ever return (two
+    # uppercase letters) — otherwise this would accept an arbitrary
+    # ".."-laden path segment.
+    get "/tiles/hiking_trails/:code.geojson" do
+      halt 404 unless params[:code].match?(/\A[A-Z]{2}\z/)
+
+      path = PmtilesBuilder.hiking_trails_country_path(DATA_DIR, params[:code])
+      halt 404 unless File.exist?(path)
+
+      send_file path, type: "application/geo+json"
+    end
+
    # Pinged once per page load (public/js/map.js) — url is a same-origin
    # path (not kiwix-serve's own address, which the browser can't reach
    # directly behind the reverse proxy in front of this app), proxied by
@@ -680,10 +743,8 @@ module Maptool
      halt 502, json(error: "track has no positions") if coordinates.empty?
      last = points.last

-      json(
-        type: "FeatureCollection",
-        features: [
-          { type: "Feature", geometry: { type: "LineString", coordinates: coordinates }, properties: {} },
+      features = [
+        { type: "Feature", geometry: { type: "LineString", coordinates: coordinates }, properties: { "kind" => "actual" } },
        {
          type: "Feature",
          geometry: { type: "Point", coordinates: coordinates.last },
@@ -697,7 +758,21 @@ module Maptool
          ),
        },
      ]
-      )
+
+      # Only present when the activity was started from a saved Garmin
+      # course (see LiveTrackClient#fetch) — plotted separately from the
+      # actual track ("kind" distinguishes the two LineStrings) since it's
+      # the planned route, not where the person has actually been.
+      course_coordinates = result.course&.[]("geoPoints")&.filter_map { |p| p.dig("position", "lon") && p.dig("position", "lat") && [p["position"]["lon"], p["position"]["lat"]] }
+      if course_coordinates&.any?
+        features << {
+          type: "Feature",
+          geometry: { type: "LineString", coordinates: course_coordinates },
+          properties: { "kind" => "planned", "name" => result.course["name"] },
+        }
+      end
+
+      json(type: "FeatureCollection", features: features)
    end

    get "/api/gnss/position" do
@@ -125,3 +125,7 @@ services:
    volumes:
      # :Z, same SELinux reasoning as maptool's own ./data mount above.
      - ./data/kiwix/wikipedia.zim:/data/wikipedia.zim:Z
+
+networks:
+  default:
+    enable_ipv6: true
@@ -7,9 +7,19 @@ MapTool deploys as a Podman container (via `podman compose`, driven by a
 the Gitea Actions runners run on. Two separate runners are registered
 against the Gitea instance:

-* The existing Docker-based runner (`gitea/runner:3`), labels
-  `ubuntu-latest`/`ubuntu-24.04`/`ubuntu-22.04` — runs the `check` job
-  in a fresh, isolated container per job, same as before.
+* The existing Docker-based runner (`gitea/runner:3`), label
+  `brick-build` — runs the `check` and `renovate` jobs in a fresh,
+  isolated container per job. Every label on this runner (including
+  `ubuntu-latest`/`ubuntu-24.04`/`ubuntu-22.04`, still registered but no
+  longer what `check`/`renovate` pin to) now maps to Gitea's own
+  official runner image (`docker.gitea.com/runner-images:ubuntu-latest`,
+  has Node out of the box) — an earlier `opensuse/leap:16.0` mapping for
+  `brick-build` specifically had no Node, which every step in
+  `check`/`renovate` needs (they're JS-based Actions), and briefly broke
+  both jobs (2026-09-12) until reverted to the shared `ubuntu-latest`
+  label; now that the image itself is fixed, both are pinned back to
+  `brick-build` — this machine specifically, not whichever runner
+  happens to answer to the shared label (e.g. "Gitea Runner on Cube").
 * A dedicated native runner, installed directly on the host (no Docker
  around it), label `brick-host` — runs only the `deploy` job.

@@ -202,7 +212,7 @@ const PROCESSED_LABEL = "livetrack-processed";

 function checkLiveTrackEmail() {
  const label = GmailApp.getUserLabelByName(PROCESSED_LABEL) || GmailApp.createLabel(PROCESSED_LABEL);
-  const threads = GmailApp.search(`from:noreply@garmin.com subject:LiveTrack -label:${PROCESSED_LABEL}`);
+  const threads = GmailApp.search(`from:noreply@garmin.com -label:${PROCESSED_LABEL}`);

  threads.forEach(thread => {
    // getBody() (raw HTML), not getPlainBody(): the email has no text/plain
@@ -225,9 +235,14 @@ function checkLiveTrackEmail() {

 The Gmail label (rather than marking the message read/unread) tracks which
 threads are already handled without touching the user's own inbox state.
-`subject:LiveTrack` matches regardless of the account's language — Garmin
-keeps "LiveTrack" as-is in the subject even in a localized
-("Sledujte LiveTrack používateľa ...") one.
+No `subject:LiveTrack` filter on the search — despite Gmail's own
+substring-match documentation for `subject:`, that filter empirically
+returned zero threads against a real, currently-arriving LiveTrack email
+whose subject does contain the word ("Sledujte LiveTrack používateľa
+...", confirmed 2026-09-20), so it's left out entirely — the regex match
+below is what actually narrows this down to real LiveTrack emails with a
+usable session link, `from:noreply@garmin.com` alone is deliberately
+broad.

 Set the trigger from the editor: clock icon on the left (Triggers) → *Add
 Trigger* → function `checkLiveTrackEmail`, time-driven, "Minutes timer",
@@ -71,18 +71,91 @@ and similar, varying by region):

 [source,shell]
 ----
-pmtiles extract https://download.mapterhorn.com/planet.pmtiles planet-extract.pmtiles --bbox=west,south,east,north --maxzoom=15
+pmtiles extract https://download.mapterhorn.com/planet.pmtiles planet-extract.pmtiles --bbox=west,south,east,north --maxzoom=13 --overfetch=0
 # only if a regional chunk covers the bbox too (see download_urls.json) —
 # most bboxes hit exactly one, a bbox straddling a chunk boundary hits two:
-pmtiles extract https://download.mapterhorn.com/<chunk>.pmtiles chunk-extract.pmtiles --bbox=west,south,east,north --maxzoom=15
+pmtiles extract https://download.mapterhorn.com/<chunk>.pmtiles chunk-extract.pmtiles --bbox=west,south,east,north --maxzoom=13 --overfetch=0
 pmtiles merge planet-extract.pmtiles chunk-extract.pmtiles data/terrain.pmtiles
 ----

+`--overfetch=0`: the default (0.05) merges nearby byte ranges into fewer,
+bigger requests to save round-trips — for `planet.pmtiles` (global z0-12,
+tens of GB) over a bbox spanning several countries this can collapse the
+whole extract into a *single* multi-GB request with no way to resume after
+a mid-transfer HTTP/2 stream reset. `--overfetch=0` trades that one
+fragile mega-request for many small ones instead (spread over
+`--download-threads`, default 4) — slower end to end, but a dropped
+connection only loses one small request's worth of progress, not the
+whole extract.
+
+`--maxzoom=13`: raster DEM tiles don't compress away like vector ones do
+(every tile is a real image, even over flat/empty terrain), so each extra
+zoom level roughly quadruples storage — the app's own build
+(`PmtilesBuilder::TERRAIN_MAX_ZOOM`) caps at 13, each regional chunk's
+own native minzoom, rather than the online hillshade layer's z15. A
+12-country selection at z15 was headed well past 181GB; z13 is still
+plenty for the hillshade toggle and the planned slope readout.
+
 Tiles are 512px WebP, not the 256px PNG this app's *online* Terrarium
 source uses — `public/js/dem.js`'s own point-elevation lookups
 (`shadow.js`'s terrain-shadow overlay) read the actual decoded tile
 size rather than assuming one, so this isn't a problem either way.

+== Offline hiking trails
+
+The sidebar's "Hiking trails" overlay works online out of the box
+(waymarkedtrails.org raster tiles, `public/js/hiking_trails.js`) —
+clicking a trail fires a one-off Overpass query for its name/colour/
+network/distance. For it to work offline too, one `data/hiking_trails/
+<CODE>.geojson` per country is generated automatically as the last step
+of every `offline.pmtiles` build (`Maptool::HikingTrails`,
+`lib/maptool/hiking_trails.rb`), straight from the *same* per-country
+`.osm.pbf` files already downloaded for `offline.pmtiles` itself — no
+separate download, no third-party service:
+
+[source,shell]
+----
+osmium tags-filter country.osm.pbf r/route=hiking -o hiking.osm.pbf
+osmium add-locations-to-ways hiking.osm.pbf -o hiking-located.osm.pbf
+osmium cat hiking-located.osm.pbf -f opl,locations_on_ways=true,add_metadata=false -o hiking.opl
+----
+
+`add-locations-to-ways` matters: a plain Geofabrik PBF's ways only carry
+bare node *references*, not coordinates, so skipping this step silently
+produces ways with empty x/y in the OPL output and every route gets
+dropped for having no usable geometry — not an error, just wrong output
+(verified against a real extract before this was caught). No general OSM
+tool stitches a route relation's member ways into one line for you
+(routes are a semantic grouping, not a geometry type), so
+`HikingTrails.parse_opl` does that walk itself — the same thing
+waymarkedtrails.org and this app's own online Overpass click handler
+already do.
+
+Best-effort per country: an extraction problem on one country's PBF logs
+a warning and is skipped rather than failing the whole `offline.pmtiles`
+build, or even the other countries in the same selection, over what's a
+bonus overlay, not the core map (`PmtilesBuilder.extract_hiking_trails`).
+Cached the same way `geofabrik_cache` is (skipped once a country's own
+extract is already newer than its source `.osm.pbf`), so growing the
+region selection by one country only extracts that one. Coordinates are
+rounded to 5 decimal places (~1m, plenty for a rendered line) — Slovakia
+alone is ~3000 routes, ~30MB unrounded.
+
+One file per country rather than one combined file: `GET /api/hiking-trails`
+lists which country codes have an extract (`countries: [...]`), and the
+Overlays panel's "Hiking trails" item turns that into a checklist —
+each ticked country fetches its own `GET /tiles/hiking_trails/<CODE>.geojson`
+only then, not on page load and not for countries never ticked. Offline
+click hit-tests the loaded vector layer(s) directly
+(`queryRenderedFeatures`) instead of querying Overpass, so it resolves
+instantly with no network at all. `rake hiking:trails[pbf,out]` runs the
+extraction by hand against one `.osm.pbf` for testing.
+
+`DELETE /api/offline-tiles` removes the whole `data/hiking_trails/`
+directory along with `offline.pmtiles` and the Geofabrik cache — there's
+no separate delete/rebuild route for it, since it's not an independent
+build.
+
 == In-app regeneration

 A logged-in user can also generate both files above from the app
@@ -286,6 +286,50 @@ own work (a map viewer, not a publisher of NPS-branded content):
  resource — included here only because it was shared alongside the
  typography notes above.

+== Arrowhead (shield) logo colors
+
+Unrelated to anything this app renders — noted here only because it came up
+in conversation (wanting exact colors to 3D-print the NPS arrowhead) and
+this doc is already the dumping ground for NPS-ecosystem color/graphic-identity
+facts. Per NPS's own graphic identity standards (Harpers Ferry Center), the
+arrowhead uses three official Pantone spot colors plus white:
+
+[cols="2,2,1,1"]
+|===
+| Element | Pantone | Hex (converted) | Nearest RAL Classic
+
+| Mountain
+| Dark Rust, PMS 1615 C
+| `#8b4720`
+| RAL 2013 Pearl orange (`#923E25`)
+
+| Sky
+| Medium Rust, PMS 1605 C
+| `#a65523`
+| RAL 8023 Orange brown (`#A45729`)
+
+| Trees / grass
+| Dark Green, PMS 553 C
+| `#284734`
+| RAL 6012 Black green (`#2F3D3A`)
+
+| Bison, lake, snowfield, type
+| White
+| `#ffffff`
+| RAL 9016 Traffic white (`#F1F1EA`) — RAL has no pure white
+|===
+
+Hex values are third-party Pantone→RGB conversions, not something NPS
+publishes directly (their style guide only specifies PMS codes). RAL codes
+are the closest match by RGB distance against the RAL Classic chart — same
+caveat, not an official NPS-endorsed mapping, just the nearest available
+code for filament/paint shopping. Source: NPS Graphic Identity and Style
+Guides (https://www.nps.gov/subjects/hfc/nps-graphic-identity-and-style-guides.htm),
+FAQs About Arrowhead Artwork
+(https://www.nps.gov/subjects/hfc/faqs-about-arrowhead-artwork.htm). Use of
+the arrowhead symbol itself is controlled by law/regulation/policy — see
+the FAQ page before printing/distributing anything bearing it.
+
 == NPMap4 (the older, Leaflet-based generation)

 https://www.nps.gov/lib/npmap.js/4.2.1/ — predecessor to npmap5,
@@ -51,6 +51,20 @@ overview's polar pan limit, but MapLibre 6's `Map` no longer exposes
 `.transform` at all — guarded to skip that (cosmetic) adjustment
 instead of throwing when it's absent.

+Also vendored under `public/vendor/` — MIT-licensed, attribution
+required (`LICENSE` included alongside):
+
+[cols="1,1,2"]
+|===
+| Library | Version | Source
+
+| maplibre-gl-lanes (offline hiking trails, `public/js/hiking_trails.js`
+— trails sharing a path drawn as parallel lanes); its `dist/*.mjs`
+build, minus the trailing `sourceMappingURL` comment
+| 1.3.0
+| https://github.com/c0nsumer/maplibre-gl-lanes
+|===
+
 Also vendored under `public/vendor/` — MIT-licensed (© 2013 Panayiotis
 Lipiridis), attribution required (this notice satisfies that):

@@ -0,0 +1,181 @@
+require "open3"
+require "tmpdir"
+require "json"
+require_relative "track_stats"
+
+module Maptool
+  # Prototype: extracts route=hiking relations (name/colour/network/operator,
+  # full member-way geometry) straight out of a Geofabrik .osm.pbf — the same
+  # file PmtilesBuilder already downloads per country for offline.pmtiles, so
+  # this needs no separate download or third-party service. Three osmium
+  # subprocess steps do the heavy lifting (osmium is already a server
+  # dependency, see PmtilesBuilder/docs/development.adoc):
+  #
+  #  1. `osmium tags-filter FILE r/route=hiking -o hiking.osm.pbf` — pulls
+  #     out just the hiking relations *and* (by default, no -R) every way/
+  #     node they reference, so the output is small and self-contained.
+  #  2. `osmium add-locations-to-ways` — a plain Geofabrik PBF's ways only
+  #     carry bare node *references* (ids), not coordinates; this resolves
+  #     each way's node ids against the node objects in the same file and
+  #     rewrites the way with real coordinates attached. Verified against a
+  #     real extract (Macedonia) that skipping this step silently produces
+  #     ways with empty x/y (`n123xy`, no numbers) in the OPL output below —
+  #     not an error, just wrong output, so easy to miss without checking.
+  #  3. `osmium cat hiking.osm.pbf -f opl,locations_on_ways=true,add_metadata=false`
+  #     — OPL is a plain-text, one-object-per-line format (see
+  #     https://osmcode.org/opl-file-format/); locations_on_ways (now that
+  #     step 2 actually populated them) embeds each way's node coordinates
+  #     directly in its own line, so no separate node-id -> [lon,lat] table
+  #     needs building, just two passes over text.
+  #
+  # No general OSM tool stitches a route relation's member ways into one
+  # line for you (routes are a semantic grouping, not a geometry type) —
+  # every hiking-trail renderer, including this app's own Overpass-based
+  # click handler (public/js/hiking_trails.js) and waymarkedtrails.org
+  # itself, does this same member-way walk by hand.
+  module HikingTrails
+    class ExtractError < StandardError; end
+
+    ROUTE_TAGS = %w[name description ref colour network operator].freeze
+
+    def self.osmium_bin
+      ENV.fetch("OSMIUM_BIN", "osmium")
+    end
+
+    # pbf_path: a Geofabrik-style .osm.pbf, e.g. one of
+    # PmtilesBuilder.cached_extracts' own files. Returns a GeoJSON
+    # FeatureCollection (MultiLineString per relation, one sub-line per
+    # member way — not one big concatenated LineString, since a relation's
+    # ways aren't always contiguous/ordered and jumping across a gap would
+    # draw a spurious straight connector).
+    def self.extract(pbf_path)
+      Dir.mktmpdir("maptool-hiking-trails") do |dir|
+        filtered = File.join(dir, "hiking.osm.pbf")
+        run!(osmium_bin, "tags-filter", pbf_path, "r/route=hiking", "-o", filtered)
+
+        located = File.join(dir, "hiking-located.osm.pbf")
+        run!(osmium_bin, "add-locations-to-ways", filtered, "-o", located)
+
+        opl_path = File.join(dir, "hiking.opl")
+        run!(osmium_bin, "cat", located, "-f", "opl,locations_on_ways=true,add_metadata=false", "-o", opl_path)
+
+        parse_opl(File.read(opl_path))
+      end
+    end
+
+    # Pure — no subprocess — so it's cheaply testable against a canned OPL
+    # fixture, same "keep the real logic testable without the real tool
+    # installed" reasoning OverpassPois.to_geojson already gives for staying
+    # separate from OverpassPois.fetch.
+    def self.parse_opl(text)
+      ways = {} # way id -> [[lon, lat], ...]
+      relations = [] # { tags:, members: [{type:, id:}, ...] }
+
+      text.each_line do |line|
+        fields = line.chomp.split(" ")
+        head = fields.first
+        next unless head
+
+        case head[0]
+        when "w"
+          ways[head[1..].to_i] = way_coordinates(fields)
+        when "r"
+          tags = tags_field(fields)
+          relations << { id: head[1..].to_i, tags: tags, members: members_field(fields) } if tags["route"] == "hiking"
+        end
+      end
+
+      features = relations.filter_map { |relation| relation_feature(relation, ways) }
+      { "type" => "FeatureCollection", "features" => features }
+    end
+
+    def self.relation_feature(relation, ways)
+      lines = relation[:members]
+              .select { |member| member[:type] == "w" }
+              .filter_map { |member| ways[member[:id]] }
+              .select { |coords| coords.size >= 2 }
+      return nil if lines.empty?
+
+      distance = lines.sum { |coords| TrackStats.compute(coords)["distance_meters"] }
+      tags = relation[:tags]
+      properties = {
+        "id" => relation[:id],
+        "name" => tags["name"] || tags["description"],
+        "distance_meters" => distance.round(1),
+      }
+      ROUTE_TAGS.each { |key| properties[key] ||= tags[key] }
+
+      {
+        "type" => "Feature",
+        "properties" => properties.compact,
+        # Rounded to 5 decimal places (~1m) — full OSM float precision
+        # (~1cm) is pointless for a rendered line and roughly doubles the
+        # size of every coordinate pair once this many-country GeoJSON is
+        # actually served to a browser.
+        "geometry" => { "type" => "MultiLineString", "coordinates" => round_coordinates(lines) },
+      }
+    end
+    private_class_method :relation_feature
+
+    def self.round_coordinates(lines)
+      lines.map { |coords| coords.map { |lon, lat| [lon.round(5), lat.round(5)] } }
+    end
+    private_class_method :round_coordinates
+
+    def self.field(fields, letter)
+      fields.find { |f| f.start_with?(letter) }
+    end
+    private_class_method :field
+
+    def self.tags_field(fields)
+      raw = field(fields, "T")&.delete_prefix("T") || ""
+      return {} if raw.empty?
+
+      raw.split(",").to_h { |pair| pair.split("=", 2).map { |part| unescape(part.to_s) } }
+    end
+    private_class_method :tags_field
+
+    def self.members_field(fields)
+      raw = field(fields, "M")&.delete_prefix("M") || ""
+      return [] if raw.empty?
+
+      raw.split(",").map do |member|
+        { type: member[0], id: member[1..].split("@", 2).first.to_i }
+      end
+    end
+    private_class_method :members_field
+
+    # "n123x14.123y49.456,n124x14.130y49.460,..." -> [[14.123, 49.456], ...].
+    # A member id with no embedded location (shouldn't happen with
+    # locations_on_ways=true and -R omitted, but a way with a dangling/
+    # missing node reference is possible in real-world data) is skipped
+    # rather than raising — one bad node shouldn't drop the whole route.
+    def self.way_coordinates(fields)
+      raw = field(fields, "N")&.delete_prefix("N") || ""
+      return [] if raw.empty?
+
+      raw.split(",").filter_map do |node_ref|
+        match = node_ref.match(/\An\d+x(?<lon>-?[\d.]+)y(?<lat>-?[\d.]+)\z/)
+        [match[:lon].to_f, match[:lat].to_f] if match
+      end
+    end
+    private_class_method :way_coordinates
+
+    # OPL escapes space/newline/comma/equals/@/% as %<hex>% (see
+    # https://osmcode.org/opl-file-format/#_encoding) — only tag keys/
+    # values and usernames can contain them; the field-letter prefixes and
+    # id/comma/@ separators we split on above are never themselves escaped.
+    def self.unescape(str)
+      str.gsub(/%([0-9a-fA-F]{1,6})%/) { [Regexp.last_match(1).to_i(16)].pack("U") }
+    end
+    private_class_method :unescape
+
+    def self.run!(*args)
+      stdout, stderr, status = Open3.capture3(*args)
+      raise ExtractError, "#{args.first} exited with status #{status.exitstatus}: #{[stdout, stderr].map(&:strip).reject(&:empty?).join("\n")}" unless status.success?
+    rescue Errno::ENOENT, Errno::EACCES => e
+      raise ExtractError, "could not run '#{args.first}' (#{e.message}) — is osmium-tool installed and on PATH?"
+    end
+    private_class_method :run!
+  end
+end
@@ -1,5 +1,6 @@
 require "net/http"
 require "json"
+require "time"

 module Maptool
  # Fetches a Garmin LiveTrack session's track and metadata.
@@ -18,7 +19,7 @@ module Maptool
    USER_AGENT = "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0 Safari/537.36"
    PUSH_PATTERN = /self\.__next_f\.push\((\[.*?\])\)<\/script>/m

-    Result = Struct.new(:points, :session, keyword_init: true)
+    Result = Struct.new(:points, :session, :course, keyword_init: true)

    def self.fetch(session_id, token)
      new.fetch(session_id, token)
@@ -29,6 +30,10 @@ module Maptool
    # if that part wasn't found even though points were (seen in practice:
    # session details are consistently present alongside points, but nothing
    # here depends on that holding forever).
+    # `course`: the planned route (name/geoPoints), or nil — only present
+    # when the activity was actually started from a saved Garmin course
+    # (session["courseIds"] is how the page itself knows to fetch one; a
+    # plain unplanned activity has neither).
    def fetch(session_id, token)
      payloads = parse_payloads(fetch_html(session_id, token))

@@ -36,18 +41,42 @@ module Maptool
      raise FetchError, "no track points found (session invalid or expired?)" unless points

      session = search(payloads) { |node| node if node["sessionName"] }
+      # First of possibly several — a LiveTrack session only ever follows
+      # the one course it was started from.
+      course = search(payloads) { |node| node["courses"].first if node["courses"].is_a?(Array) && !node["courses"].empty? }

-      Result.new(points: clean(points), session: clean(session))
+      Result.new(points: clean(points), session: clean(session), course: clean(course))
    end

    # Distance/duration/activity type come from the last track point (its
    # totals are cumulative for the whole session), name/type from the
    # session details — nil-safe throughout since either can be missing.
    #
-    # "active": Garmin doesn't set a session's `end` until the activity is
-    # actually stopped, so its absence means the session is still recording
-    # — inferred from the one (already-ended) session this was built
-    # against, not verified against a session actually caught mid-activity.
+    # "active": originally `session["end"].nil?`, on the assumption Garmin
+    # doesn't set `end` until the activity actually stops — disproven
+    # against a real still-recording session (2026-09-20): `end` was
+    # already non-nil, set to exactly `start + 24h`, the share link's own
+    # expiry, not an actual end time. Two signals now, both verified live
+    # against that same session:
+    #
+    # * `end` itself, once it's actually in the past — watched the same
+    #   session update it from that 24h placeholder to within a second of
+    #   the last point's own time, immediately after the activity was
+    #   saved on the watch. Authoritative and near-instant when present,
+    #   so this is checked first.
+    # * failing that (still showing the future placeholder — an abandoned
+    #   session never gets saved, so `end` never moves), recency of the
+    #   last track point: Garmin posts one roughly every
+    #   `postTrackPointFrequency` seconds (~15, observed) while genuinely
+    #   still recording, so one older than ACTIVE_WITHIN means signal was
+    #   lost a while ago (same "looks ended until it isn't" behavior
+    #   Garmin's own LiveTrack page shows in that case).
+    #
+    # Both must agree the session is live — `end` already in the past
+    # means stopped even if the last point is only seconds old (exactly
+    # the save-immediately-after-the-last-point case above).
+    ACTIVE_WITHIN = 30 * 60 # seconds
+
    def self.summarize(result)
      last = result.points.last || {}
      session = result.session || {}
@@ -56,12 +85,23 @@ module Maptool
        "activity_type" => last["activityType"],
        "distance_meters" => last["totalDistanceMeters"],
        "duration_secs" => last["totalDurationSecs"],
-        "active" => session["end"].nil?,
+        "active" => active?(last["dateTime"], session["end"]),
        "start" => session["start"],
        "end" => session["end"],
      }
    end

+    def self.active?(last_point_time, session_end)
+      return false unless last_point_time
+
+      now = Time.now.utc
+      return false if session_end && Time.parse(session_end) <= now
+
+      Time.parse(last_point_time) > now - ACTIVE_WITHIN
+    rescue ArgumentError, TypeError
+      false
+    end
+
    private

    # The RSC payload serializes an absent field as the literal string
@@ -12,7 +12,15 @@ module Maptool
  module OverpassPois
    class FetchError < StandardError; end

-    OVERPASS_API = "https://overpass-api.de/api/interpreter".freeze
+    # Same three public mirrors public/js/hiking_trails.js races — tried in
+    # turn here instead, falling through to the next on any failure: the
+    # shared free instances regularly 504/429 under load, and a plugin run
+    # is a one-off click, not worth threads to race them.
+    OVERPASS_APIS = [
+      "https://overpass-api.de/api/interpreter",
+      "https://overpass.kumi.systems/api/interpreter",
+      "https://overpass.private.coffee/api/interpreter",
+    ].freeze

    # Each entry: an Overpass tag filter -> { label:, icon:, color: }, used
    # both to build the query (unioning every filter) and to label/style
@@ -53,8 +61,23 @@ module Maptool
    # bbox: [south, west, north, east] (Overpass's own axis order).
    def self.fetch(bbox, timeout: 60)
      query = build_query(bbox, timeout: timeout)
-      uri = URI(OVERPASS_API)
-      response = Net::HTTP.post_form(uri, "data" => query)
+      errors = OVERPASS_APIS.map do |url|
+        return post(URI(url), query, timeout)
+      rescue FetchError, Net::OpenTimeout, Net::ReadTimeout, SystemCallError, SocketError, OpenSSL::SSL::SSLError, JSON::ParserError => e
+        "#{URI(url).host}: #{e.message}"
+      end
+      raise FetchError, errors.join("; ")
+    end
+
+    def self.post(uri, query, timeout)
+      # overpass-api.de answers Net::HTTP's default "Ruby" User-Agent with
+      # a 406 (verified 2026-10-09) — any identifying UA gets through.
+      request = Net::HTTP::Post.new(uri, "User-Agent" => "maptool (Overpass camper POIs plugin)")
+      request.set_form_data("data" => query)
+      # read_timeout past the query's own [timeout:] — Net::HTTP's default
+      # 60s equals it, so a big viewport could hit Net::ReadTimeout just as
+      # Overpass was about to answer (a country-sized bbox measured ~57s).
+      response = Net::HTTP.start(uri.host, uri.port, use_ssl: true, read_timeout: timeout + 30) { |http| http.request(request) }
      raise FetchError, "unexpected response #{response.code}" unless response.is_a?(Net::HTTPSuccess)

      JSON.parse(response.body)
@@ -65,8 +65,13 @@ module Maptool
      south, west, north, east = bbox
      args = ["--south=#{south}", "--west=#{west}", "--north=#{north}", "--east=#{east}"]

-      stdout, _stderr, status = Open3.capture3(command, *args, chdir: plugin_dir)
-      raise RunError, "plugin exited with status #{status.exitstatus}" unless status.success?
+      stdout, stderr, status = Open3.capture3(command, *args, chdir: plugin_dir)
+      # First stderr line too — for a Ruby plugin that's the exception
+      # message (e.g. "...: unexpected response 406"), the only clue to why.
+      unless status.success?
+        reason = stderr.lines.first&.strip
+        raise RunError, ["plugin exited with status #{status.exitstatus}", reason].compact.reject(&:empty?).join(": ")
+      end

      geojson = JSON.parse(stdout)
      raise RunError, "plugin did not print a GeoJSON FeatureCollection" unless geojson.is_a?(Hash) && geojson["type"] == "FeatureCollection"
@@ -5,6 +5,7 @@ require "json"
 require "tmpdir"
 require "fileutils"
 require "etc"
+require_relative "hiking_trails"

 module Maptool
  # Regenerates data/offline.pmtiles and data/terrain.pmtiles for the
@@ -88,11 +89,15 @@ module Maptool
    # archive" story via go-pmtiles, unrelated to the basemap swap.
    MAPTERHORN_MANIFEST_URL = "https://download.mapterhorn.com/download_urls.json"
    MAPTERHORN_PLANET_NAME = "planet.pmtiles"
-    # Matches the online hillshade layer's own cap (public/js/overlays.js's
-    # ONLINE_TERRAIN_TILES source, maxzoom: 15) — applied uniformly even
-    # though some Mapterhorn chunks natively offer more, so the offline
-    # experience doesn't vary in detail from one region to the next.
-    TERRAIN_MAX_ZOOM = 15
+    # Deliberately *below* the online hillshade layer's own cap
+    # (public/js/overlays.js's ONLINE_TERRAIN_TILES source, maxzoom: 15) —
+    # raster DEM tiles don't compress away like vector ones do, so every
+    # extra zoom level roughly quadruples storage. z13 is each regional
+    # chunk's own native minzoom (see the comment above), so this is the
+    # cheapest useful cut: one raster level per chunk, not a 15-13=2-level
+    # pyramid on top of it. Bumped into a 181GB terrain.pmtiles for a
+    # 5-country selection before this was lowered — see docs/development.adoc.
+    TERRAIN_MAX_ZOOM = 13

    OFFLINE_STATUS = { state: "idle" }
    TERRAIN_STATUS = { state: "idle" }
@@ -285,12 +290,66 @@ module Maptool
      run_planetiler!("--osm-path=#{osm_path}", "--output=#{tmp_path}", "--download", "--threads=#{Etc.nprocessors}")
      File.rename(tmp_path, File.join(data_dir, "offline.pmtiles"))
      File.write(offline_meta_path(data_dir), JSON.generate(sources: sources.map { |s| s.slice("code", "slug", "last_modified") }))
+
+      report_step.call("extracting hiking trails")
+      extract_hiking_trails(sources, data_dir)
    ensure
      FileUtils.remove_entry(scratch_dir) if scratch_dir && Dir.exist?(scratch_dir)
      File.delete(tmp_path) if tmp_path && File.exist?(tmp_path)
    end
    private_class_method :extract_offline

+    # One GeoJSON per country (data/hiking_trails/<CODE>.geojson), not one
+    # merged file — the frontend only ever needs to show a country at a
+    # time the viewer actually picks (see HikingTrailsControl's country
+    # checklist), and a combined multi-country file was needlessly making
+    # every viewer fetch every selected country's trails regardless.
+    #
+    # Runs over the same per-country .osm.pbf files `sources` above already
+    # downloaded/cached for offline.pmtiles itself — no separate download.
+    # Cached the same way geofabrik_cache is: skipped for a country whose
+    # extract is already newer than its source .osm.pbf, so growing the
+    # region selection by one country only extracts that one, not every
+    # already-covered country all over again.
+    #
+    # Best-effort per country: an extraction problem (a malformed PBF
+    # region, an osmium hiccup) shouldn't fail the whole offline.pmtiles
+    # build, or even the other countries in this same selection, over
+    # what's a bonus overlay, not the core map.
+    def self.extract_hiking_trails(sources, data_dir)
+      FileUtils.mkdir_p(hiking_trails_dir(data_dir))
+      sources.each do |source|
+        out_path = hiking_trails_country_path(data_dir, source["code"])
+        next if File.exist?(out_path) && File.mtime(out_path) >= File.mtime(source["path"])
+
+        tmp_path = "#{out_path}.tmp"
+        begin
+          File.write(tmp_path, JSON.generate(HikingTrails.extract(source["path"])))
+          File.rename(tmp_path, out_path)
+        rescue HikingTrails::ExtractError => e
+          File.delete(tmp_path) if File.exist?(tmp_path)
+          warn "hiking trails extraction failed for #{source["code"]}, skipping: #{e.message}"
+        end
+      end
+    end
+    private_class_method :extract_hiking_trails
+
+    def self.hiking_trails_dir(data_dir)
+      File.join(data_dir, "hiking_trails")
+    end
+
+    def self.hiking_trails_country_path(data_dir, code)
+      File.join(hiking_trails_dir(data_dir), "#{code}.geojson")
+    end
+
+    # Country codes with an already-extracted offline hiking-trails file,
+    # sorted — not necessarily the same as the *current* region selection
+    # (accumulates like geofabrik_cache does; a country deselected after
+    # being built once is left alone rather than swept up here).
+    def self.hiking_trails_countries(data_dir)
+      Dir.glob(File.join(hiking_trails_dir(data_dir), "*.geojson")).map { |path| File.basename(path, ".geojson") }.sort
+    end
+
    # Renders a report_step string like "fetching PL (3/4) — done: SK, CZ —
    # pending: HU" — so GET .../build-status shows not just "it's running"
    # but which of the current build's sources is in flight and which are
@@ -438,6 +497,7 @@ module Maptool

      File.delete(File.join(data_dir, "offline.pmtiles")) if File.exist?(File.join(data_dir, "offline.pmtiles"))
      File.delete(offline_meta_path(data_dir)) if File.exist?(offline_meta_path(data_dir))
+      FileUtils.remove_entry(hiking_trails_dir(data_dir)) if Dir.exist?(hiking_trails_dir(data_dir))
      cache_dir = geofabrik_cache_dir(data_dir)
      FileUtils.remove_entry(cache_dir) if Dir.exist?(cache_dir)
    end
@@ -513,7 +573,17 @@ module Maptool
      extracts = sources.each_with_index.map do |item, i|
        report_step.call(progress_step("extracting #{item["name"]}", labels, i))
        extract_path = File.join(scratch_dir, "extract-#{i}.pmtiles")
-        run_pmtiles!("extract", item["url"], extract_path, "--region=#{region_path}", "--maxzoom=#{TERRAIN_MAX_ZOOM}")
+        # --overfetch=0: go-pmtiles' default (0.05) merges nearby byte
+        # ranges into fewer, bigger HTTP requests to save round-trips —
+        # for planet.pmtiles (global z0-12, tens of GB) covering a
+        # multi-country selection that collapsed the whole extract into
+        # a *single* ~60GB request, which then had no way to resume after
+        # an HTTP/2 stream reset 11 minutes in (see the "died again"
+        # 2026-09-12 build). Disabling merging trades that one fragile,
+        # unresumable mega-request for many small ones spread over
+        # --download-threads (default 4) — slower on a clean run, but no
+        # longer one dropped stream away from losing 20 minutes of transfer.
+        run_pmtiles!("extract", item["url"], extract_path, "--region=#{region_path}", "--maxzoom=#{TERRAIN_MAX_ZOOM}", "--overfetch=0")
        extract_path
      end

@@ -621,11 +691,23 @@ module Maptool
      ENV.fetch("PLANETILER_JAR", "/usr/local/lib/planetiler.jar")
    end

+    # go-pmtiles' extract logs one progress line per chunk fetched
+    # ("fetching N dirs, M chunks, K requests") — fine on a terminal where
+    # it overwrites itself, but captured non-interactively that's one line
+    # per chunk, easily hundreds of thousands of characters for a big
+    # region. The actual failure is always at the end, so keep only the
+    # tail — same story for osmium/planetiler's own chatty stdout.
+    OUTPUT_TAIL_LINES = 40
+
    # Some CLI tools (go-pmtiles included) write their actual error to
    # stdout rather than stderr — combine both rather than risk raising a
    # BuildError with nothing useful in it.
    def self.command_output(stdout, stderr)
-      [stdout, stderr].map(&:strip).reject(&:empty?).join("\n")
+      lines = [stdout, stderr].map(&:strip).reject(&:empty?).join("\n").lines
+      return lines.join if lines.size <= OUTPUT_TAIL_LINES
+
+      omitted = lines.size - OUTPUT_TAIL_LINES
+      "(#{omitted} earlier lines omitted)\n#{lines.last(OUTPUT_TAIL_LINES).join}"
    end
    private_class_method :command_output

@@ -397,6 +397,68 @@ html, body {
  visibility: visible;
 }

+/* Docked detail panel for a clicked hiking trail — replaces a map-anchored
+   Popup (which routinely covered up the very trail line it described) with
+   a fixed side panel, same "click info moves off the map" idea
+   track_profile.js already established for clicking a GPX track line
+   (TrackProfilePanel). .trail-panel__body gets the exact padding
+   .maplibregl-popup-content used (15px 10px) so routeHtml()'s own output —
+   built for that popup, including its header's canceling negative margin —
+   renders here unchanged; no separate panel-flavored template needed. */
+.trail-panel {
+  position: fixed;
+  top: 0;
+  right: 0;
+  bottom: 0;
+  width: 300px;
+  max-width: 90vw;
+  background: #fff;
+  border-left: 1px solid #ddd;
+  box-shadow: -2px 0 8px rgba(0, 0, 0, 0.15);
+  z-index: 10;
+}
+
+.trail-panel__body {
+  height: 100%;
+  box-sizing: border-box;
+  overflow-y: auto;
+  padding: 15px 10px;
+  font-size: 13px;
+}
+
+.trail-panel__close {
+  position: absolute;
+  top: 6px;
+  right: 6px;
+  border: none;
+  border-radius: 50%;
+  background: rgba(255, 255, 255, 0.85);
+  font-size: 18px;
+  line-height: 1;
+  padding: 2px 7px;
+  cursor: pointer;
+}
+
+/* First breakpoint in this file. Below it the same panel docks to the
+   bottom edge instead of the right one — a fixed-width side panel would
+   otherwise eat most of a phone-width map, the exact "popup dominates the
+   screen" problem this panel was meant to fix in the first place. */
+@media (max-width: 640px) {
+  .trail-panel {
+    top: auto;
+    left: 0;
+    right: 0;
+    bottom: 0;
+    width: auto;
+    max-width: none;
+    max-height: 50vh;
+    border-left: none;
+    border-top: 1px solid #ddd;
+    border-radius: 8px 8px 0 0;
+    box-shadow: 0 -2px 8px rgba(0, 0, 0, 0.15);
+  }
+}
+
 .offline-data-panel__body {
  padding: 8px 12px;
 }
@@ -542,6 +604,14 @@ html, body {
  font-size: 12px;
 }

+.offline-data-panel__status--error {
+  white-space: pre-wrap;
+  word-break: break-word;
+  max-height: 200px;
+  overflow-y: auto;
+  color: #b3261e;
+}
+
 .offline-data-panel__update-badge {
  color: #b8860b;
 }
@@ -1346,6 +1416,14 @@ html, body {
  color: #fff;
 }

+.hiking-trail-popup__swatch {
+  flex-shrink: 0;
+  width: 14px;
+  height: 14px;
+  border-radius: 50%;
+  border: 1px solid rgba(255, 255, 255, 0.6);
+}
+
 .gpx-popup__header-icon {
  flex-shrink: 0;
  width: 18px;
@@ -1563,6 +1641,22 @@ html, body {
  font-size: 12px;
 }

+.hiking-trail-countries {
+  display: flex;
+  flex-wrap: wrap;
+  gap: 4px 12px;
+  list-style: none;
+  margin: 0;
+  padding: 0;
+}
+
+.hiking-trail-countries__item label {
+  display: flex;
+  align-items: center;
+  gap: 4px;
+  cursor: pointer;
+}
+
 .livetrack-panel__list {
  flex: 1;
  overflow-y: auto;
@@ -0,0 +1,442 @@
+import { WALKING_ICON } from "/js/icons.js";
+import { firstSymbolLayerId } from "/js/radar.js";
+import { escapeHtml } from "/js/gpx.js";
+import { lineLength, formatDistance } from "/js/measure.js";
+import { buildLineGraph, orderLanesAsync, LaneLayer } from "/vendor/maplibre-gl-lanes/maplibre-gl-lanes.mjs";
+
+// Overpass has permissive CORS (verified: Access-Control-Allow-Origin: *),
+// so this queries it directly from the browser — no server-side proxy
+// needed, same "public API, no key" story as the Nominatim search already
+// hits from here. One query per click (not per pan/move like the
+// Wikipedia layer's live refetch), so this stays well within Overpass's
+// shared rate limits.
+//
+// Three independent public mirrors (also CORS-open, verified), raced with
+// Promise.any rather than called one at a time — the shared free instances
+// vary a lot in load from one moment to the next, and a multi-second wait
+// on a single one was the main complaint. Whichever answers first wins;
+// the others are simply left to finish and get GC'd, not worth the extra
+// AbortController plumbing for a single one-off per-click request.
+const OVERPASS_APIS = [
+  "https://overpass-api.de/api/interpreter",
+  "https://overpass.kumi.systems/api/interpreter",
+  "https://overpass.private.coffee/api/interpreter",
+];
+const CLICK_RADIUS_M = 40;
+// OSM colour tag values are free text (untrusted) — only used as a CSS
+// background if they look like an actual color (hex or a plain word),
+// never interpolated unchecked into a style attribute.
+const SAFE_COLOR = /^(#[0-9a-fA-F]{3,8}|[a-zA-Z]+)$/;
+
+// Pre-rendered raster tiles, not vector — waymarkedtrails.org already
+// colors each route by its OSM `colour` tag (the KST/KČT-style paint-blaze
+// colors used in Slovakia/Czechia), falling back to plain red where a route
+// has none, so there's no styling to do here ourselves. Used whenever no
+// offline extract is available at all — same "quietly renders nothing
+// without a network" story as the Wikipedia/Radar/Contour lines overlays.
+const ONLINE_SOURCE_ID = "hiking-trails-online";
+const ONLINE_LAYER_ID = "hiking-trails-online-line";
+const TILE_URL = "https://tile.waymarkedtrails.org/hiking/{z}/{x}/{y}.png";
+const ATTRIBUTION =
+  'Trails &copy; <a href="https://waymarkedtrails.org" target="_blank">Waymarked Trails</a> (CC-BY-SA), map data &copy; OpenStreetMap contributors';
+const OPACITY = 0.85;
+
+// Offline: real vector trails for each country the viewer actually picks,
+// GeoJSON generated at build time by Maptool::HikingTrails straight
+// from the same Geofabrik .osm.pbf offline.pmtiles itself is built from
+// (see lib/maptool/hiking_trails.rb, PmtilesBuilder.extract_hiking_trails)
+// — no network needed, and no waiting on Overpass for click details either
+// (hit-tested locally via LaneLayer.queryLane instead, see _handleClick
+// below). One file per country rather than one combined file: a viewer
+// covering a dozen countries' worth of offline map data rarely wants all
+// of their hiking trails loaded at once, so this is opt-in per country
+// instead.
+//
+// Drawn with maplibre-gl-lanes rather than a plain line layer: a stretch
+// of path several marked routes share (very common with KST blazes) is
+// otherwise one line drawn over and over, only the topmost color visible.
+// Lanes puts each route in its own parallel lane instead. It needs routes
+// sharing a path to share exact vertices, which OSM relations over shared
+// ways already do. One LaneLayer over every picked country, not one per
+// country, so lanes at a border stay ordered together. Doesn't drape over
+// 3D terrain (sinks under raised ground, warns on the console) — a known
+// limitation of the library, not worth working around for an overlay.
+const LANES_LAYER_ID = "hiking-trails-lanes";
+const LANE_SIZES = () => ({ spacing: 3.5, width: 3, casingWidth: 0.5 });
+function offlineUrl(code) {
+  return `/tiles/hiking_trails/${code}.geojson`;
+}
+
+// waymarkedtrails.org's own fallback for an untagged route.
+const DEFAULT_TRAIL_COLOR = "#c1272d";
+// Real-world `colour` values seen in production data (see the 2026-09-13
+// extraction against SK.osm.pbf) — anything outside this set (typos like
+// "yelllow", multi-value combos like "blue, yellow", stray hex codes) falls
+// back to DEFAULT_TRAIL_COLOR rather than being trusted as a CSS value
+// straight from OSM tag text.
+const KNOWN_TRAIL_COLORS = new Set(["red", "yellow", "blue", "green", "orange", "purple", "brown", "black", "white", "grey", "gray", "darkblue"]);
+
+function normalizedTrailColor(raw) {
+  if (!raw) return DEFAULT_TRAIL_COLOR;
+  const trimmed = raw.trim();
+  if (KNOWN_TRAIL_COLORS.has(trimmed.toLowerCase())) return trimmed.toLowerCase();
+  return /^#[0-9a-fA-F]{3,8}$/.test(trimmed) ? trimmed : DEFAULT_TRAIL_COLOR;
+}
+
+// Online mode's highlight outline for whichever route(s) the last click
+// matched — drawn as its own separate source/layer (real geometry, from the
+// Overpass response), since the raster tiles have no paintable features to
+// highlight at all. Offline lanes use LaneLayer.setHighlight instead. Same "yellow outline on a picked
+// route" treatment the earlier SVG prototype visualization used.
+const HIGHLIGHT_SOURCE_ID = "hiking-trails-highlight";
+const HIGHLIGHT_LAYER_ID = "hiking-trails-highlight-line";
+
+// An Overlays panel item — a plain on/off checkbox (raster overlay) until
+// offline extracts exist for at least one country, at which point it
+// becomes an expandable per-country checklist instead (same expand shape
+// as RadarControl), since a viewer with a dozen countries' worth of
+// offline map data rarely wants all of their hiking trails loaded, let
+// alone parsed by the browser, at once.
+export class HikingTrailsControl {
+  constructor(map) {
+    this._map = map;
+    this._active = false; // the online-mode checkbox's own state
+    this._offlineCountries = []; // codes with an extract available on the server
+    this._selectedCountries = new Set(); // codes currently shown, offline mode
+    this._trailData = new Map(); // code -> fetched GeoJSON, kept across toggles/style swaps
+    this._routeInfo = new Map(); // String(relation id) -> feature properties, for the panel
+    this._lanes = null; // the current LaneLayer, null when no country is shown
+
+    map.on("click", (event) => this._handleClick(event));
+
+    this._panel = document.getElementById("trail-panel");
+    this._panelBody = this._panel.querySelector(".trail-panel__body");
+    this._panel.querySelector(".trail-panel__close").addEventListener("click", () => this._hidePanel());
+
+    // setStyle() (switching Online/Offline) tears down all custom sources/
+    // layers — put whatever was showing back, same as every other
+    // Overlays control. The highlight is transient (tied to whichever
+    // trail is showing in the panel, if any) — simpler to just drop it
+    // here than try to carry it across a style swap.
+    map.on("style.load", () => {
+      if (this._active) this._addOnlineLayer();
+      this._clearHighlight();
+      if (this._selectedCountries.size > 0) this._rebuildLanes();
+    });
+  }
+
+  mount(li) {
+    li.innerHTML = `
+      <div class="overlays-panel__row">
+        <input type="checkbox" class="overlays-panel__toggle">
+        <span class="overlays-panel__icon">${WALKING_ICON}</span>
+        <button type="button" class="overlays-panel__name">Hiking trails</button>
+      </div>
+      <div class="overlays-panel__details" hidden>
+        <ul class="hiking-trail-countries"></ul>
+      </div>
+    `;
+    this._checkbox = li.querySelector(".overlays-panel__toggle");
+    this._nameButton = li.querySelector(".overlays-panel__name");
+    this._details = li.querySelector(".overlays-panel__details");
+    this._countryList = li.querySelector(".hiking-trail-countries");
+
+    this._checkbox.addEventListener("change", (event) => this._toggleOnline(event.target.checked));
+    this._nameButton.addEventListener("click", () => {
+      if (this._offlineCountries.length === 0) return; // nothing to expand into yet
+      const expanding = this._details.hidden;
+      this._details.hidden = !expanding;
+      this._nameButton.setAttribute("aria-expanded", String(expanding));
+    });
+  }
+
+  // Called once map.js's GET /api/hiking-trails check resolves. Switches
+  // this item from "online raster, plain on/off" to "offline vector,
+  // pick your countries" — the two are mutually exclusive rather than
+  // both offered at once, since once a real local extract exists there's
+  // no reason to still fall back to a third-party tile server for any of
+  // it.
+  setOfflineCountries(countries) {
+    this._offlineCountries = countries;
+    if (countries.length === 0) return;
+
+    if (this._active) this._toggleOnline(false);
+    this._checkbox.hidden = true;
+
+    this._countryList.innerHTML = countries
+      .map(
+        (code) => `
+          <li class="hiking-trail-countries__item">
+            <label>
+              <input type="checkbox" class="hiking-trail-countries__toggle" value="${code}">
+              ${code}
+            </label>
+          </li>
+        `,
+      )
+      .join("");
+    this._countryList.querySelectorAll(".hiking-trail-countries__toggle").forEach((input) => {
+      input.addEventListener("change", (event) => this._toggleCountry(event.target.value, event.target.checked));
+    });
+  }
+
+  _toggleOnline(active) {
+    this._active = active;
+    if (active) this._addOnlineLayer();
+    else this._removeOnlineLayer();
+  }
+
+  async _toggleCountry(code, active) {
+    if (!active) {
+      this._selectedCountries.delete(code);
+      this._rebuildLanes();
+      return;
+    }
+    this._selectedCountries.add(code);
+    if (!this._trailData.has(code)) {
+      let geojson;
+      try {
+        geojson = await (await fetch(offlineUrl(code))).json();
+      } catch {
+        return; // degrade quietly, same story as every other optional layer here
+      }
+      // Normalized once here so an untrustworthy `colour` tag value never
+      // reaches the layer's color directly — same reasoning gpx.js's own
+      // feature.properties.color ||= TRACK_COLOR normalization gives.
+      for (const feature of geojson.features) {
+        feature.properties.color = normalizedTrailColor(feature.properties.colour);
+      }
+      this._trailData.set(code, geojson);
+      if (!this._selectedCountries.has(code)) return; // toggled back off while fetching
+    }
+    this._rebuildLanes();
+  }
+
+  // Rebuilt from scratch on every country toggle and style swap (setStyle
+  // drops custom layers too) — lane order depends on every route drawn, so
+  // there's no cheaper incremental path. Ordering runs in a worker; a newer
+  // rebuild started meanwhile wins, same token guard as _handleOnlineClick.
+  async _rebuildLanes() {
+    const build = (this._lanesBuild = {});
+    const features = [...this._selectedCountries].flatMap((code) => this._trailData.get(code)?.features || []);
+    let graph = null;
+    if (features.length > 0) {
+      graph = buildLineGraph(features, { routeProperty: "id" });
+      await orderLanesAsync(graph);
+    }
+    if (this._lanesBuild !== build) return;
+
+    this._hidePanel();
+    if (this._map.getLayer(LANES_LAYER_ID)) this._map.removeLayer(LANES_LAYER_ID);
+    this._lanes = null;
+    this._routeInfo = new Map(features.map((feature) => [String(feature.properties.id), feature.properties]));
+    if (!graph) return;
+
+    this._lanes = new LaneLayer({ id: LANES_LAYER_ID, graph, sizes: LANE_SIZES, casingColor: "rgba(255, 255, 255, 0.8)" });
+    // Below labels (same firstSymbolLayerId spot contour.js/radar.js use),
+    // so place names/POI icons stay readable on top of the trail lines.
+    this._map.addLayer(this._lanes, firstSymbolLayerId(this._map));
+  }
+
+  _handleClick(event) {
+    if (this._selectedCountries.size > 0) this._handleOfflineClick(event);
+    else if (this._active) this._handleOnlineClick(event);
+  }
+
+  // The lanes have real geometry to hit-test directly — no network
+  // round-trip, so this resolves instantly. Each route has its own lane, so
+  // a click picks exactly one, highlighted by the layer itself. A genuine
+  // miss just closes an already-open panel rather than showing a "not
+  // found" message, same as clicking empty space anywhere else on the map.
+  _handleOfflineClick(event) {
+    const hit = this._lanes?.queryLane(event.point, 8);
+    const info = hit && this._routeInfo.get(String(hit.route));
+    if (!info) {
+      this._hidePanel();
+      return;
+    }
+    this._lanes.setHighlight(hit.route);
+    this._showPanel(routeHtml(info));
+  }
+
+  _showPanel(html) {
+    this._panelBody.innerHTML = html;
+    this._panel.hidden = false;
+  }
+
+  _hidePanel() {
+    if (this._panel.hidden) return;
+    this._panel.hidden = true;
+    this._clearHighlight();
+  }
+
+  // The raster tiles have no queryable features (they're pixels), so
+  // "what trail is this" is answered with a one-off Overpass query instead
+  // of a MapLibre feature hit-test — an `around` search rather than an
+  // exact point match, since a click rarely lands exactly on the (already
+  // pixel-thick) rendered line.
+  async _handleOnlineClick(event) {
+    const { lng, lat } = event.lngLat;
+    this._showPanel(`<p class="gpx-popup__category">Looking for trails…</p>`);
+    // A newer click's request replaces this one while Overpass is still
+    // answering — same "in-flight response arrives after it's already
+    // stale" guard the old Popup-identity check gave, just keyed off a
+    // fresh token each click instead of a fresh Popup instance.
+    const request = (this._onlineRequest = {});
+
+    let relations;
+    try {
+      relations = await fetchNearbyRoutes(lng, lat);
+    } catch {
+      if (this._onlineRequest === request) this._panelBody.innerHTML = `<p class="gpx-popup__category">Could not reach Overpass.</p>`;
+      return;
+    }
+    if (this._onlineRequest !== request) return;
+
+    if (relations.length === 0) {
+      this._panelBody.innerHTML = `<p class="gpx-popup__category">No hiking trail found here.</p>`;
+      return;
+    }
+    this._panelBody.innerHTML = relations.map((relation) => routeHtml(overpassRouteInfo(relation))).join("<hr>");
+    this._setHighlight(relations.map((relation) => ({ geometry: routeGeometry(relation), color: normalizedTrailColor(relation.tags?.colour) })));
+  }
+
+  _addOnlineLayer() {
+    if (this._map.getSource(ONLINE_SOURCE_ID)) return;
+
+    this._map.addSource(ONLINE_SOURCE_ID, {
+      type: "raster",
+      tiles: [TILE_URL],
+      tileSize: 256,
+      maxzoom: 17,
+      attribution: ATTRIBUTION,
+    });
+    // Below labels (same firstSymbolLayerId spot contour.js/radar.js use),
+    // so place names/POI icons stay readable on top of the trail lines.
+    this._map.addLayer(
+      { id: ONLINE_LAYER_ID, type: "raster", source: ONLINE_SOURCE_ID, paint: { "raster-opacity": OPACITY } },
+      firstSymbolLayerId(this._map),
+    );
+  }
+
+  _removeOnlineLayer() {
+    if (this._map.getLayer(ONLINE_LAYER_ID)) this._map.removeLayer(ONLINE_LAYER_ID);
+    if (this._map.getSource(ONLINE_SOURCE_ID)) this._map.removeSource(ONLINE_SOURCE_ID);
+  }
+
+  // features: an array of { geometry, color } — geometry a GeoJSON
+  // LineString or MultiLineString (mixed is fine), color the trail's own
+  // (already-normalized) colour — everything the last click matched, drawn
+  // as one highlight layer (a wider outline in the trail's own color,
+  // rather than a fixed color that would repaint it) on top of the base
+  // trail rendering.
+  _setHighlight(features) {
+    const data = {
+      type: "FeatureCollection",
+      features: features.map(({ geometry, color }) => ({ type: "Feature", properties: { color }, geometry })),
+    };
+    const source = this._map.getSource(HIGHLIGHT_SOURCE_ID);
+    if (source) {
+      source.setData(data);
+      return;
+    }
+    this._map.addSource(HIGHLIGHT_SOURCE_ID, { type: "geojson", data });
+    this._map.addLayer({
+      id: HIGHLIGHT_LAYER_ID,
+      type: "line",
+      source: HIGHLIGHT_SOURCE_ID,
+      layout: { "line-cap": "round", "line-join": "round" },
+      paint: { "line-color": ["get", "color"], "line-width": 5, "line-opacity": 0.9 },
+    });
+  }
+
+  _clearHighlight() {
+    this._lanes?.setHighlight(null);
+    if (this._map.getLayer(HIGHLIGHT_LAYER_ID)) this._map.removeLayer(HIGHLIGHT_LAYER_ID);
+    if (this._map.getSource(HIGHLIGHT_SOURCE_ID)) this._map.removeSource(HIGHLIGHT_SOURCE_ID);
+  }
+}
+
+// way(around:...) finds candidate ways near the click, then rel(bw...)
+// walks backward from those to their parent relations — the same
+// find-the-way-then-its-relation shape as clicking a route on
+// waymarkedtrails.org's own site. `out geom` inlines each member way's
+// full coordinate list right on the relation, so no separate stitching
+// step is needed to get real geometry back.
+async function queryOverpass(url, query) {
+  const response = await fetch(url, { method: "POST", body: `data=${encodeURIComponent(query)}` });
+  if (!response.ok) throw new Error(`overpass ${response.status}`);
+  return response.json();
+}
+
+async function fetchNearbyRoutes(lng, lat) {
+  const query = `[out:json][timeout:15];way(around:${CLICK_RADIUS_M},${lat},${lng})->.w;rel(bw.w)["route"="hiking"];out geom;`;
+  const data = await Promise.any(OVERPASS_APIS.map((url) => queryOverpass(url, query)));
+  return (data.elements || []).filter((element) => element.type === "relation");
+}
+
+// OSM doesn't tag a route's length directly — summed from each member
+// way's own geometry instead, same haversine-sum measure.js's own Measure
+// tool uses for a hand-drawn line. Shared endpoints between adjacent ways
+// get walked twice, same as how a real hike over those ways would. Mirrors
+// Maptool::HikingTrails.relation_feature's own distance calc server-side
+// (lib/maptool/hiking_trails.rb) — this is the online, no-server-file path.
+function routeDistance(relation) {
+  return (relation.members || [])
+    .filter((member) => member.type === "way" && member.geometry)
+    .reduce((total, member) => total + lineLength(member.geometry.map((point) => [point.lon, point.lat])), 0);
+}
+
+// Same member-way walk as routeDistance above, collecting coordinates
+// instead of summing them — the online click highlight's geometry source,
+// since there's no vector feature to read it back from the way the offline
+// layer's own queryRenderedFeatures result already carries one.
+function routeGeometry(relation) {
+  const lines = (relation.members || [])
+    .filter((member) => member.type === "way" && member.geometry)
+    .map((member) => member.geometry.map((point) => [point.lon, point.lat]));
+  return { type: "MultiLineString", coordinates: lines };
+}
+
+// Adapts a raw Overpass relation into the same shape offline GeoJSON
+// features' properties already carry (lib/maptool/hiking_trails.rb's own
+// ROUTE_TAGS + distance_meters + id) — one HTML builder (routeHtml) below
+// serves both instead of two near-identical ones.
+function overpassRouteInfo(relation) {
+  const tags = relation.tags || {};
+  return {
+    id: relation.id,
+    name: tags.name,
+    description: tags.description,
+    colour: tags.colour,
+    network: tags.network,
+    operator: tags.operator,
+    ref: tags.ref,
+    distance_meters: routeDistance(relation),
+  };
+}
+
+function routeHtml(info) {
+  const name = info.name || info.description || "Hiking trail";
+  const swatch = SAFE_COLOR.test(info.colour || "")
+    ? `<span class="hiking-trail-popup__swatch" style="background:${info.colour}"></span>`
+    : "";
+  const meta = [formatDistance(info.distance_meters || 0)];
+  if (info.ref) meta.push(`#${info.ref}`);
+  if (info.network) meta.push(info.network);
+  if (info.operator) meta.push(escapeHtml(info.operator));
+
+  const parts = [
+    `<div class="gpx-popup__header"><strong>${escapeHtml(name)}</strong>${swatch}</div>`,
+    `<p class="gpx-popup__category">${meta.filter(Boolean).join(" · ")}</p>`,
+  ];
+  // description already used as the title above when there's no name — only
+  // shown again here as its own line if there both is a name *and* a
+  // description to add, so it's never rendered twice for the common
+  // no-name case.
+  if (info.name && info.description) parts.push(`<p class="gpx-popup__description">${escapeHtml(info.description)}</p>`);
+  parts.push(
+    `<p class="gpx-popup__link"><a href="https://www.openstreetmap.org/relation/${info.id}" target="_blank" rel="noopener noreferrer">View on OpenStreetMap →</a></p>`,
+  );
+  return parts.join("");
+}
@@ -328,7 +328,11 @@ const FISHING_ICON = `
 const SCENIC_VIEWPOINT_ICON = `
 <svg viewBox="0 0 22 22" fill="currentColor"><g transform="translate(4.000000, 0.000000)"><path d="M3.2,11c0,1.2-0.9,2.2-2.1,2.2c-1.2,0-2.1-1-2.1-2.2 c0-1.2,0.9-2.2,2.1-2.2C2.2,8.8,3.2,9.8,3.2,11"/><path d="M4.6,10.4v1.3l10.6,0.8v-3L4.6,10.4"/><path d="M2.3,7.5l1.1,0.7L7.7,2L5.3,0.5L2.3,7.5"/><path d="M4.4,9.8l7.9-3.8l-1.4-2.6L3.8,8.6L4.4,9.8z"/><path d="M2.3,14.5l1.1-0.7l4.3,6.2l-2.4,1.5L2.3,14.5"/><path d="M3.8,13.4l0.6-1.2l7.9,3.8l-1.4,2.6L3.8,13.4"/></g></svg>`;

-const WALKING_ICON = `
+// Exported (unlike the other POI glyphs around it) — also used as the
+// Overlays panel's Hiking trails glyph (hiking_trails.js), same "reuse an
+// existing NPS-sourced pictogram" story as WILDERNESS_ICON above rather
+// than hand-drawing another one.
+export const WALKING_ICON = `
 <svg viewBox="0 0 22 22" fill="currentColor"><path d="M10.4,3.6c1,0,1.8-0.8,1.7-1.8c0-1-0.8-1.8-1.8-1.7c-1,0-1.8,0.8-1.7,1.8C8.6,2.8,9.5,3.6,10.4,3.6z"/><path d="M16.5,9.5L13.9,8l-2.2-3.4c-0.3-0.4-0.9-0.8-1.5-0.7C9.7,4,9.3,4.2,9,4.4L5.8,7.7C5.7,7.8,5.6,8,5.6,8.1l-0.4,3.6 c0,0,0,0.1,0,0.1c0,0.4,0.4,0.8,0.8,0.8c0.4,0,0.7-0.4,0.8-0.8l0.3-3.1l1.1-1.1l-1,8.6l-1.9,4.1c-0.1,0.1-0.1,0.3-0.1,0.5 c0,0.7,0.6,1.2,1.2,1.2c0.5,0,0.9-0.3,1.1-0.7l2-4.4c0-0.1,0.2-0.4,0.2-0.5l0.2-2.1l2.1,6.9c0.2,0.5,0.6,0.8,1.2,0.8 c0.7,0,1.2-0.6,1.2-1.2c0-0.1,0-0.1,0-0.2L11.5,11l0.4-3.1l0.8,1.3c0.1,0.1,0.1,0.2,0.2,0.2l2.8,1.6c0.1,0,0.2,0.1,0.4,0.1 c0.4,0,0.8-0.4,0.8-0.8C16.9,9.8,16.7,9.6,16.5,9.5z"/></svg>`;

 const GUIDED_TOURS_ICON = `
@@ -5,6 +5,11 @@ import { notifySidePanelOpen, onlyOneSidePanelOpen } from "/js/panels.js";
 const SESSIONS_URL = "/api/livetrack/sessions";
 const TRACK_SOURCE = "livetrack-track";
 const TRACK_COLOR = "#7209b7";
+// The planned route (only present when the activity was started from a
+// saved Garmin course, see LiveTrackClient#fetch) — dashed and muted so it
+// reads as a reference line, not more recorded data next to the actual
+// track's own color.
+const PLANNED_COLOR = "#888";
 // Garmin devices post a new point roughly every 15s (postTrackPointFrequency
 // in the session data) — polling twice that often would just re-fetch the
 // same 400+KB page for nothing most of the time.
@@ -171,11 +176,22 @@ export class LiveTrackPanelControl {
    if (this._map.getSource(TRACK_SOURCE)) return;

    this._map.addSource(TRACK_SOURCE, { type: "geojson", data: geojson });
+    // Added before the actual track's own line layer so it paints
+    // underneath — the recorded track is the thing that actually matters
+    // when the two overlap.
+    this._map.addLayer({
+      id: `${TRACK_SOURCE}-planned`,
+      type: "line",
+      source: TRACK_SOURCE,
+      filter: ["all", ["==", ["geometry-type"], "LineString"], ["==", ["get", "kind"], "planned"]],
+      layout: { "line-cap": "round", "line-join": "round" },
+      paint: { "line-color": PLANNED_COLOR, "line-width": 2, "line-dasharray": [2, 2] },
+    });
    this._map.addLayer({
      id: `${TRACK_SOURCE}-line`,
      type: "line",
      source: TRACK_SOURCE,
-      filter: ["==", ["geometry-type"], "LineString"],
+      filter: ["all", ["==", ["geometry-type"], "LineString"], ["==", ["get", "kind"], "actual"]],
      layout: { "line-cap": "round", "line-join": "round" },
      paint: { "line-color": TRACK_COLOR, "line-width": 3 },
    });
@@ -607,6 +607,11 @@ fetch("/api/terrain-tiles")
  })
  .catch(() => {});

+fetch("/api/hiking-trails")
+  .then((response) => response.json())
+  .then(({ countries }) => overlaysControl.setHikingTrailsOfflineCountries(countries))
+  .catch(() => {});
+
 fetch("/api/kiwix")
  .then((response) => response.json())
  .then(({ available }) => overlaysControl.setWikiAvailable(available))
@@ -317,7 +317,9 @@ function haversine([lng1, lat1], [lng2, lat2]) {
  return 2 * EARTH_RADIUS_M * Math.asin(Math.sqrt(a));
 }

-function lineLength(points) {
+// Exported — also used by hiking_trails.js to total up an OSM route
+// relation's member ways into one distance, same haversine-sum approach.
+export function lineLength(points) {
  let total = 0;
  for (let i = 1; i < points.length; i++) total += haversine(points[i - 1], points[i]);
  return total;
@@ -347,7 +349,8 @@ function polygonArea(points) {
  return Math.abs((area * EARTH_RADIUS_M * EARTH_RADIUS_M) / 2);
 }

-function formatDistance(meters) {
+// Exported — also used by hiking_trails.js's route-details popup.
+export function formatDistance(meters) {
  if (meters === 0) return "";
  return meters >= 1000 ? `${(meters / 1000).toFixed(2)} km` : `${Math.round(meters)} m`;
 }
@@ -206,23 +206,31 @@ class DataFileRow {
    this._refreshStatus();
  }

+  // Single place that writes to _statusEl, so the error styling (pre-wrap,
+  // scrollable, red — see style.css) never stays stuck on once a build's
+  // failure message has scrolled past into a normal status line.
+  _setStatus(text, isError = false) {
+    this._statusEl.textContent = text;
+    this._statusEl.classList.toggle("offline-data-panel__status--error", isError);
+  }
+
  async _refreshStatus() {
    let data;
    try {
      data = await (await fetch(this._statusUrl)).json();
    } catch {
-      this._statusEl.textContent = "Could not check status.";
+      this._setStatus("Could not check status.");
      return;
    }

    if (!data.available) {
-      this._statusEl.textContent = "Not generated yet.";
+      this._setStatus("Not generated yet.");
      this._deleteButton.hidden = true;
      return;
    }

    const updated = new Date(data.mtime).toLocaleString([], { dateStyle: "short", timeStyle: "short" });
-    this._statusEl.textContent = `${formatBytes(data.size)} · updated ${updated}${this._formatMeta(data.meta)}`;
+    this._setStatus(`${formatBytes(data.size)} · updated ${updated}${this._formatMeta(data.meta)}`);
    this._deleteButton.hidden = !isLoggedIn();
    this._checkUpdate();
  }
@@ -274,7 +282,7 @@ class DataFileRow {
  // Called by OfflineDataControl once RegionPicker's Apply has saved a
  // new selection — not tied to a button of this row's own.
  async triggerBuild() {
-    this._statusEl.textContent = "Checking…";
+    this._setStatus("Checking…");
    try {
      // false (not null/true — see offline_update_available? in
      // pmtiles_builder.rb) means the just-saved selection matches what's
@@ -291,17 +299,17 @@ class DataFileRow {
      // couldn't tell — fall through and build rather than silently skip
    }

-    this._statusEl.textContent = "Starting…";
+    this._setStatus("Starting…");
    try {
      const response = await fetch(this._buildUrl, { method: "POST" });
      const data = await response.json().catch(() => ({}));
      if (!response.ok) throw new Error(data.error || `build failed: ${response.status}`);
    } catch (err) {
-      this._statusEl.textContent = err.message;
+      this._setStatus(err.message, true);
      return;
    }

-    this._statusEl.textContent = "Building…";
+    this._setStatus("Building…");
    this._poll();
  }

@@ -318,13 +326,13 @@ class DataFileRow {
      }

      if (status.state === "running") {
-        this._statusEl.textContent = formatRunning(status);
+        this._setStatus(formatRunning(status));
        this._poll();
        return;
      }

      if (status.state === "error") {
-        this._statusEl.textContent = `Build failed: ${status.message}`;
+        this._setStatus(`Build failed: ${status.message}`, true);
      } else {
        this._refreshStatus();
      }
@@ -5,6 +5,7 @@ import { svgToImageData, badgeImageId, escapeHtml } from "/js/gpx.js";
 import { RadarControl } from "/js/radar.js";
 import { ShadowControl } from "/js/shadow.js";
 import { ContourControl } from "/js/contour.js";
+import { HikingTrailsControl } from "/js/hiking_trails.js";

 const ICON_IMAGE_SIZE = 48; // rasterized once at this size, rendered much smaller by icon-size below
 const ICON_SIZE = 0.3; // 48 * 0.3 = ~14px, sized to sit inside the marker badge below
@@ -184,6 +185,7 @@ export class OverlaysControl {
    this._radar = new RadarControl(map);
    this._shadow = new ShadowControl(map);
    this._contour = new ContourControl(map);
+    this._hikingTrails = new HikingTrailsControl(map);
    this._wikiEnabled = false; // the checkbox's own state
    this._wikiMoveHandler = null; // the moveend listener driving its live refetch, while enabled
    this._wikiRequestSeq = 0; // ignores an in-flight refetch a newer one has already superseded
@@ -217,13 +219,15 @@ export class OverlaysControl {
      <li class="overlays-panel__item overlays-panel__item--expandable"></li>
      <li class="overlays-panel__item overlays-panel__item--expandable"></li>
      <li class="overlays-panel__item"></li>
+      <li class="overlays-panel__item overlays-panel__item--expandable"></li>
    `;
-    const [hillshadeItem, wikiItem, radarItem, shadowItem, contourItem] = list.children;
+    const [hillshadeItem, wikiItem, radarItem, shadowItem, contourItem, hikingTrailsItem] = list.children;
    this._hillshade.mount(hillshadeItem);
    this._mountWiki(wikiItem);
    this._radar.mount(radarItem);
    this._shadow.mount(shadowItem);
    this._contour.mount(contourItem);
+    this._hikingTrails.mount(hikingTrailsItem);

    onlyOneSidePanelOpen(this._panel, () => this._icon.classList.remove("active"));

@@ -241,6 +245,10 @@ export class OverlaysControl {
    this._hillshade.setOfflineAvailable(available);
  }

+  setHikingTrailsOfflineCountries(countries) {
+    this._hikingTrails.setOfflineCountries(countries);
+  }
+
  // Called by map.js's PitchToggleControl whenever the 3D pitch toggle
  // changes, so raised terrain follows the camera tilt rather than needing
  // the "Terrain shading" checkbox re-clicked to notice.
@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2026 Steve Vigneau
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
@@ -39,6 +39,19 @@ class AppTest < Minitest::Test
    assert_equal({ "available" => false }, json_body(response))
  end

+  def test_hiking_trails_reports_no_countries_when_none_extracted_yet
+    response = request.get("/api/hiking-trails")
+    assert_equal({ "countries" => [] }, json_body(response))
+  end
+
+  def test_hiking_trails_file_404s_for_a_country_with_no_extract
+    assert_equal 404, request.get("/tiles/hiking_trails/SK.geojson").status
+  end
+
+  def test_hiking_trails_file_404s_for_a_malformed_country_code
+    assert_equal 404, request.get("/tiles/hiking_trails/../../etc/passwd.geojson").status
+  end
+
  def test_kiwix_reports_unavailable_when_no_url_configured
    response = request.get("/api/kiwix")
    assert_equal({ "available" => false, "url" => "" }, json_body(response))
@@ -0,0 +1,125 @@
+require_relative "test_helper"
+require "maptool/hiking_trails"
+
+# No real osmium calls — extract() is a thin subprocess-plus-parse wrapper
+# (same "not independently tested" reasoning OverpassPois.fetch gets), but
+# parse_opl is pure text in, GeoJSON out, and that's the part actually worth
+# protecting: the OPL escaping rules and the way-id -> relation-member
+# stitching are easy to get subtly wrong and osmium isn't installed in every
+# environment this test suite runs in.
+class HikingTrailsTest < Minitest::Test
+  def test_parse_opl_builds_a_multilinestring_from_member_way_geometry
+    opl = <<~OPL
+      w1 Thighway=path Nn10x20.087y49.179,n11x20.088y49.18
+      w2 Thighway=path Nn11x20.088y49.18,n12x20.089y49.181
+      r1 Troute=hiking,type=route,name=Rysy Mw1@,w2@
+    OPL
+
+    features = Maptool::HikingTrails.parse_opl(opl)["features"]
+
+    assert_equal 1, features.size
+    feature = features.first
+    assert_equal "MultiLineString", feature["geometry"]["type"]
+    assert_equal [[[20.087, 49.179], [20.088, 49.18]], [[20.088, 49.18], [20.089, 49.181]]], feature["geometry"]["coordinates"]
+    assert_equal "Rysy", feature["properties"]["name"]
+  end
+
+  def test_parse_opl_skips_relations_that_are_not_route_hiking
+    opl = <<~OPL
+      w1 Thighway=path Nn10x20.087y49.179,n11x20.088y49.18
+      r1 Ttype=multipolygon Mw1@outer
+    OPL
+
+    assert_empty Maptool::HikingTrails.parse_opl(opl)["features"]
+  end
+
+  def test_parse_opl_falls_back_to_description_when_there_is_no_name
+    opl = <<~OPL
+      w1 Thighway=path Nn10x20.087y49.179,n11x20.088y49.18
+      r1 Troute=hiking,type=route,description=Rázc.%20%pri%20%Žabom%20%potoku%20%-%20%Rysy Mw1@
+    OPL
+
+    feature = Maptool::HikingTrails.parse_opl(opl)["features"].first
+
+    assert_equal "Rázc. pri Žabom potoku - Rysy", feature["properties"]["name"]
+  end
+
+  def test_parse_opl_unescapes_commas_and_equals_in_tag_values
+    opl = <<~OPL
+      w1 Thighway=path Nn10x20.087y49.179,n11x20.088y49.18
+      r1 Troute=hiking,type=route,name=Salt%2c%%20%Pepper%3d%Co Mw1@
+    OPL
+
+    feature = Maptool::HikingTrails.parse_opl(opl)["features"].first
+
+    assert_equal "Salt, Pepper=Co", feature["properties"]["name"]
+  end
+
+  def test_parse_opl_carries_over_colour_network_operator_ref
+    opl = <<~OPL
+      w1 Thighway=path Nn10x20.087y49.179,n11x20.088y49.18
+      r1 Troute=hiking,type=route,name=Trail,colour=red,network=rwn,operator=KST,ref=0933 Mw1@
+    OPL
+
+    properties = Maptool::HikingTrails.parse_opl(opl)["features"].first["properties"]
+
+    assert_equal "red", properties["colour"]
+    assert_equal "rwn", properties["network"]
+    assert_equal "KST", properties["operator"]
+    assert_equal "0933", properties["ref"]
+  end
+
+  def test_parse_opl_computes_distance_from_member_way_geometry
+    # Roughly 111.2m per 0.001 degree of latitude at the equator.
+    opl = <<~OPL
+      w1 Thighway=path Nn10x0.0y0.0,n11x0.0y0.001
+      r1 Troute=hiking,type=route,name=Trail Mw1@
+    OPL
+
+    distance = Maptool::HikingTrails.parse_opl(opl)["features"].first["properties"]["distance_meters"]
+
+    assert_in_delta 111.2, distance, 1.0
+  end
+
+  def test_parse_opl_drops_a_relation_whose_member_ways_are_all_missing
+    opl = <<~OPL
+      r1 Troute=hiking,type=route,name=Ghost Mw999@
+    OPL
+
+    assert_empty Maptool::HikingTrails.parse_opl(opl)["features"]
+  end
+
+  def test_parse_opl_carries_the_osm_relation_id_for_cross_country_dedup
+    opl = <<~OPL
+      w1 Thighway=path Nn10x20.087y49.179,n11x20.088y49.18
+      r1246205 Troute=hiking,type=route,name=Trail Mw1@
+    OPL
+
+    feature = Maptool::HikingTrails.parse_opl(opl)["features"].first
+
+    assert_equal 1246205, feature["properties"]["id"]
+  end
+
+  def test_parse_opl_rounds_coordinates_to_5_decimal_places
+    opl = <<~OPL
+      w1 Thighway=path Nn10x20.0876543210y49.1791234567,n11x20.0880000001y49.1800000009
+      r1 Troute=hiking,type=route,name=Trail Mw1@
+    OPL
+
+    coords = Maptool::HikingTrails.parse_opl(opl)["features"].first["geometry"]["coordinates"]
+
+    assert_equal [[[20.08765, 49.17912], [20.088, 49.18]]], coords
+  end
+
+  def test_parse_opl_ignores_a_dangling_member_reference_but_keeps_the_rest
+    opl = <<~OPL
+      w1 Thighway=path Nn10x20.087y49.179,n11x20.088y49.18
+      r1 Troute=hiking,type=route,name=Trail Mw1@,w999@
+    OPL
+
+    features = Maptool::HikingTrails.parse_opl(opl)["features"]
+
+    assert_equal 1, features.size
+    assert_equal 1, features.first["geometry"]["coordinates"].size
+  end
+end
@@ -16,6 +16,7 @@ class LiveTrackClientTest < Minitest::Test
    <script>self.__next_f.push([1,"6:[\\"$\\",\\"div\\",null,{}]"])</script>
    <script>self.__next_f.push([1,"9:{\\"session\\":{\\"sessionName\\":\\"Test Ride\\",\\"start\\":\\"2026-01-01T00:00:00Z\\",\\"end\\":\\"2026-01-01T01:00:00Z\\"}}"])</script>
    <script>self.__next_f.push([1,"10:{\\"unrelated\\":true,\\"nested\\":{\\"data\\":{\\"pages\\":[{\\"trackPoints\\":[{\\"position\\":{\\"lat\\":48.1,\\"lon\\":17.2},\\"dateTime\\":\\"2026-01-01T00:00:00Z\\",\\"totalDistanceMeters\\":\\"$undefined\\"},{\\"position\\":{\\"lat\\":48.2,\\"lon\\":17.3},\\"dateTime\\":\\"2026-01-01T00:01:00Z\\",\\"activityType\\":\\"CYCLING\\",\\"totalDistanceMeters\\":5000,\\"totalDurationSecs\\":600}]}]}}}"])</script>
+    <script>self.__next_f.push([1,"11:{\\"courses\\":[{\\"name\\":\\"40 km okruh\\",\\"geoPoints\\":[{\\"position\\":{\\"lat\\":48.05,\\"lon\\":17.35},\\"distanceMeters\\":0},{\\"position\\":{\\"lat\\":48.06,\\"lon\\":17.36},\\"distanceMeters\\":1000}]}]}"])</script>
    </body></html>
  HTML

@@ -49,18 +50,52 @@ class LiveTrackClientTest < Minitest::Test
    assert_equal "Test Ride", summary["session_name"]
    assert_equal "CYCLING", summary["activity_type"]
    assert_equal 5000, summary["distance_meters"]
-    refute summary["active"], "session has an end timestamp"
+    refute summary["active"], "last track point is long in the past"
  end

-  def test_summarize_marks_active_when_session_has_no_end
+  # Not session["end"].nil? (the original signal, before 2026-09-20 — see
+  # LiveTrackClient's own comment): verified live against a real,
+  # still-recording session that day, Garmin had already set `end` to
+  # exactly start + 24h (the share link's own expiry, not an end time),
+  # so that check called an active session "ended".
+  def test_summarize_marks_active_when_last_point_is_recent
    payloads = @client.send(:parse_payloads, FAKE_PAGE)
    points = @client.send(:clean, @client.send(:search, payloads) { |n| n["trackPoints"] if n["trackPoints"].is_a?(Array) })
-    session = @client.send(:clean, @client.send(:search, payloads) { |n| n if n["sessionName"] }).merge("end" => nil)
+    points[-1] = points[-1].merge("dateTime" => Time.now.utc.iso8601)
+    # end present and in the future, same shape Garmin actually sends for a
+    # session that's still live — active must come from the point, not this.
+    session = @client.send(:clean, @client.send(:search, payloads) { |n| n if n["sessionName"] })
+                      .merge("end" => (Time.now.utc + 24 * 60 * 60).iso8601)
    result = Maptool::LiveTrackClient::Result.new(points: points, session: session)

    assert Maptool::LiveTrackClient.summarize(result)["active"]
  end

+  # Verified live the same day: Garmin updates a real session's `end` from
+  # the future placeholder to within a second of the last point's own
+  # time immediately once the activity is saved on the watch — so a fresh
+  # last point alone isn't enough, `end` already being in the past has to
+  # win even then.
+  def test_summarize_marks_inactive_once_end_is_in_the_past_even_with_a_fresh_point
+    payloads = @client.send(:parse_payloads, FAKE_PAGE)
+    points = @client.send(:clean, @client.send(:search, payloads) { |n| n["trackPoints"] if n["trackPoints"].is_a?(Array) })
+    points[-1] = points[-1].merge("dateTime" => Time.now.utc.iso8601)
+    session = @client.send(:clean, @client.send(:search, payloads) { |n| n if n["sessionName"] })
+                      .merge("end" => (Time.now.utc - 1).iso8601)
+    result = Maptool::LiveTrackClient::Result.new(points: points, session: session)
+
+    refute Maptool::LiveTrackClient.summarize(result)["active"]
+  end
+
+  def test_finds_the_planned_course_alongside_the_actual_track
+    payloads = @client.send(:parse_payloads, FAKE_PAGE)
+    course = @client.send(:clean, @client.send(:search, payloads) { |n| n["courses"].first if n["courses"].is_a?(Array) && !n["courses"].empty? })
+
+    assert_equal "40 km okruh", course["name"]
+    assert_equal 2, course["geoPoints"].size
+    assert_in_delta 48.06, course["geoPoints"].last["position"]["lat"]
+  end
+
  def test_no_track_points_found_in_a_page_without_them
    points = @client.send(:search, @client.send(:parse_payloads, "<html></html>")) { |n| n["trackPoints"] if n["trackPoints"].is_a?(Array) }
    assert_nil points
@@ -47,6 +47,21 @@ class PmtilesBuilderTest < Minitest::Test
    File.write(@pmtiles_fail, "#!/bin/sh\necho 'boom' >&2\nexit 1\n")
    File.chmod(0o755, @pmtiles_fail)

+    # Mimics go-pmtiles' real extract failure mode: hundreds of progress
+    # lines before the actual error — see command_output's tail-truncation.
+    @pmtiles_fail_noisy = File.join(@bin_dir, "pmtiles-fail-noisy")
+    File.write(@pmtiles_fail_noisy, <<~SH)
+      #!/bin/sh
+      i=0
+      while [ "$i" -lt 200 ]; do
+        echo "fetching $i dirs, $i chunks, 1 requests" >&2
+        i=$((i + 1))
+      done
+      echo "stream error: stream ID 9; INTERNAL_ERROR" >&2
+      exit 1
+    SH
+    File.chmod(0o755, @pmtiles_fail_noisy)
+
    # osmium merge PBF1 PBF2 ... -o OUTPUT — output is always "-o"'s next
    # arg, unlike pmtiles' varying-position output above.
    @osmium_ok = File.join(@bin_dir, "osmium-ok")
@@ -61,6 +76,27 @@ class PmtilesBuilderTest < Minitest::Test
    SH
    File.chmod(0o755, @osmium_ok)

+    # Same shape as osmium-ok, but fails on tags-filter specifically (the
+    # first subcommand HikingTrails.extract runs) while still succeeding
+    # on merge — lets a single-country build (which never calls merge)
+    # exercise "hiking-trails extraction failed" without also breaking
+    # offline.pmtiles' own osmium use in a multi-country test.
+    @osmium_fail_tags_filter = File.join(@bin_dir, "osmium-fail-tags-filter")
+    File.write(@osmium_fail_tags_filter, <<~SH)
+      #!/bin/sh
+      echo "osmium $1" >> "$PMTILES_LOG"
+      if [ "$1" = "tags-filter" ]; then
+        echo "boom" >&2
+        exit 1
+      fi
+      prev=""
+      for arg; do
+        if [ "$prev" = "-o" ]; then echo fake > "$arg"; fi
+        prev="$arg"
+      done
+    SH
+    File.chmod(0o755, @osmium_fail_tags_filter)
+
    # Stands in for `java -jar planetiler.jar --osm-path=... --output=OUT`
    # — PLANETILER_JAR itself is irrelevant here (this fake ignores -jar's
    # argument entirely), only JAVA_BIN needs pointing at it.
@@ -173,13 +209,66 @@ class PmtilesBuilderTest < Minitest::Test
    assert_path_exists File.join(@data_dir, "offline.pmtiles")
    refute_path_exists File.join(@data_dir, "offline.tmp.pmtiles")
    assert_equal "done", Maptool::PmtilesBuilder.offline_status[:state]
-    assert_equal ["planetiler --osm-path"], log_lines
+    assert_equal ["planetiler --osm-path", "osmium tags-filter", "osmium add-locations-to-ways", "osmium cat"], log_lines
    assert_equal(
      { "sources" => [{ "code" => "SK", "slug" => "europe/slovakia", "last_modified" => "Wed, 10 Sep 2026 08:00:01 GMT" }] },
      Maptool::PmtilesBuilder.offline_meta(@data_dir),
    )
  end

+  def test_build_offline_also_writes_a_per_country_hiking_trails_geojson
+    select_regions("SK")
+    thread = Maptool::PmtilesBuilder.build_offline(data_dir: @data_dir, download_extract: fake_download)
+    thread.join
+
+    # The fake osmium binary doesn't produce real OPL output, just
+    # confirms the file lands (one per country) and is valid (empty)
+    # GeoJSON — the real parsing logic is covered by test_hiking_trails.rb
+    # against real OPL fixtures.
+    assert_equal ["SK"], Maptool::PmtilesBuilder.hiking_trails_countries(@data_dir)
+    path = Maptool::PmtilesBuilder.hiking_trails_country_path(@data_dir, "SK")
+    assert_equal({ "type" => "FeatureCollection", "features" => [] }, JSON.parse(File.read(path)))
+  end
+
+  def test_build_offline_only_re_extracts_hiking_trails_for_a_newly_added_country
+    select_regions("SK")
+    Maptool::PmtilesBuilder.build_offline(data_dir: @data_dir, download_extract: fake_download).join
+    File.write(@log, "")
+
+    select_regions("SK", "AT")
+    Maptool::PmtilesBuilder.build_offline(
+      data_dir: @data_dir,
+      download_extract: fake_download,
+      fetch_last_modified: ->(_url) { "Wed, 10 Sep 2026 08:00:01 GMT" },
+    ).join
+
+    # SK's cached extract is already newer than SK.osm.pbf (untouched
+    # since the first build), so only AT's hiking trails get (re-)extracted
+    # — SK.osm.pbf itself is also skipped by cached_extract's own
+    # Last-Modified check, "osmium merge" runs regardless since two
+    # countries are now selected.
+    assert_equal(
+      ["osmium merge", "planetiler --osm-path", "osmium tags-filter", "osmium add-locations-to-ways", "osmium cat"],
+      log_lines,
+    )
+    assert_equal %w[AT SK], Maptool::PmtilesBuilder.hiking_trails_countries(@data_dir)
+  end
+
+  # The actual reasoning: hiking trails are a bonus overlay bolted onto the
+  # existing offline.pmtiles build, not the core map — an osmium hiccup on
+  # this one step shouldn't take down an otherwise-successful build.
+  def test_build_offline_still_succeeds_when_hiking_trails_extraction_fails
+    select_regions("SK")
+    ENV["OSMIUM_BIN"] = @osmium_fail_tags_filter
+    thread = Maptool::PmtilesBuilder.build_offline(data_dir: @data_dir, download_extract: fake_download)
+    thread.join
+
+    assert_path_exists File.join(@data_dir, "offline.pmtiles")
+    assert_equal "done", Maptool::PmtilesBuilder.offline_status[:state]
+    refute_path_exists File.join(@data_dir, "hiking_trails.geojson")
+    refute_path_exists "#{File.join(@data_dir, "hiking_trails.geojson")}.tmp"
+  end
+
  # Two countries selected — osmium merge should run before planetiler,
  # each downloaded source recorded in the sidecar meta.
  def test_build_offline_merges_multiple_selected_countries
@@ -188,7 +277,14 @@ class PmtilesBuilderTest < Minitest::Test
    thread.join

    assert_equal "done", Maptool::PmtilesBuilder.offline_status[:state]
-    assert_equal ["osmium merge", "planetiler --osm-path"], log_lines
+    assert_equal(
+      [
+        "osmium merge", "planetiler --osm-path",
+        "osmium tags-filter", "osmium add-locations-to-ways", "osmium cat", # SK's own hiking-trails extraction
+        "osmium tags-filter", "osmium add-locations-to-ways", "osmium cat", # AT's own
+      ],
+      log_lines,
+    )
    codes = Maptool::PmtilesBuilder.offline_meta(@data_dir)["sources"].map { |s| s["code"] }
    assert_equal %w[SK AT], codes
  end
@@ -545,6 +641,22 @@ class PmtilesBuilderTest < Minitest::Test
    assert_match(/exited with status/, status[:message])
  end

+  # The real trigger for this: a Mapterhorn extract that failed after ~7000
+  # progress lines, producing a 500k+ character status[:message] that was
+  # unreadable in the web UI.
+  def test_build_terrain_truncates_a_noisy_command_failure
+    select_regions("ES")
+    ENV["PMTILES_BIN"] = @pmtiles_fail_noisy
+    thread = Maptool::PmtilesBuilder.build_terrain(data_dir: @data_dir, fetch_manifest: -> { fake_manifest })
+    thread.join
+
+    status = Maptool::PmtilesBuilder.terrain_status
+    assert_equal "error", status[:state]
+    assert_match(/\(\d+ earlier lines omitted\)/, status[:message])
+    assert_match(/stream error: stream ID 9/, status[:message])
+    assert_operator status[:message].length, :<, 5000
+  end
+
  def test_build_terrain_raises_when_one_is_already_running
    select_regions("ES")
    ENV["PMTILES_BIN"] = @pmtiles_ok
@@ -31,6 +31,11 @@
  <div class="profile-panel__charts"></div>
 </div>

+<div id="trail-panel" class="trail-panel" hidden>
+  <button type="button" class="trail-panel__close" aria-label="Close">&times;</button>
+  <div class="trail-panel__body"></div>
+</div>
+
 <div id="basemap-panel" class="basemap-panel" hidden>
  <div class="basemap-panel__header">
    <strong>Base map</strong>
@@ -35,6 +35,7 @@
        "/js/dem.js": "/js/dem.js?v=<%= ASSET_VERSION %>",
        "/js/gnss.js": "/js/gnss.js?v=<%= ASSET_VERSION %>",
        "/js/gpx.js": "/js/gpx.js?v=<%= ASSET_VERSION %>",
+        "/js/hiking_trails.js": "/js/hiking_trails.js?v=<%= ASSET_VERSION %>",
        "/js/icons.js": "/js/icons.js?v=<%= ASSET_VERSION %>",
        "/js/livetrack.js": "/js/livetrack.js?v=<%= ASSET_VERSION %>",
        "/js/locate.js": "/js/locate.js?v=<%= ASSET_VERSION %>",