Sonntag-Unteralpschellen
1723.1 m · net rise 184.7 m · total ascent 186.8 m · overall 10.7% · evidence quality B (good) · Sonntag · Vorarlberg · share
Shape: sustained — 32% of the climbing sits in a quarter of the distance; longest continuous stretch at 10%+ is 475 m.
Found purely from mapping and LiDAR data, and not yet matched against books, race records or lists — it may be well known to locals under a name we've never heard. It was cross-checked against the GIP.at road network, OpenStreetMap and a second terrain model, but a discovery can still be an artifact of the terrain model or the map. Treat it as a well-evidenced hypothesis until someone has ridden it. If you know this road, tell us what you found — photographs, corrections and local knowledge all welcome; the map links below let you scout it first.
Gradient ladder what do windows mean?
| Window | Maximum | Located at | |
|---|---|---|---|
| 2 m (diagnostic) | ≈40% | 0–2 m | under overhead cover terrain reads 49.4% at 541–543 m across terrain that holds no road surface (dense canopy, no bench) — excluded |
| 3 m (diagnostic) | ≈26% | 0–3 m | under overhead cover terrain reads 42.9% at 541–544 m across terrain that holds no road surface (dense canopy, no bench) — excluded |
| 5 m | ≈20% | 680–685 m | under overhead cover terrain reads 33.9% at 539–544 m across a structure and terrain that holds no road surface (dense canopy, no bench) — excluded |
| 10 m | ≈17% | 1363–1373 m | under overhead cover terrain reads 24.3% at 535–545 m across terrain that holds no road surface (dense canopy, no bench) — excluded |
| 20 m | ≈16.5% | 1362–1382 m | under overhead cover terrain reads 21.0% at 536–556 m across terrain that holds no road surface (dense canopy, no bench) — excluded |
| 25 m | ≈16.1% | 497–522 m | under overhead cover terrain reads 19.1% at 531–556 m across terrain that holds no road surface (dense canopy, no bench) — excluded |
| 50 m | ≈15.4% | 1660–1710 m | under overhead cover terrain reads 16.9% at 505–555 m across terrain that holds no road surface (dense canopy, no bench) — excluded |
| 100 m | ≈14.7% | 1290–1390 m | under overhead cover terrain reads 15.1% at 456–556 m across terrain that holds no road surface (dense canopy, no bench) — excluded |
may continue beyond end Extent detection suggests reviewing where this climb starts/ends.
Map
Check this route yourself: Google Maps route via their router · Street View at the base where coverage exists · geojson.io our exact measured line · OpenTopoMap
This climb's data: OCL JSON — the full gradient ladder, quality flags and provenance in the OpenClimb Ladder format.
Surface: GIP.at, Austria's official transport graph records no surface for this road; the map may tell you more.
Measured, not vetted. This page records what the laser record shows about the road's shape — nothing more. Nobody has necessarily ridden or inspected this road for the survey, and a page here is not a recommendation and no guarantee that the road is open, surfaced, rideable or safe. Gates, private sections, missing rights of way and hazards do not show up in elevation data. Check access and conditions on the ground and make your own judgment.
Ridden it, or know better? Submit data for this climb no account needed · Share this climb
Route colour = gradient over a 25 m window: <10% 10–20% 20–25% ≥25%
© OpenStreetMap contributors · topo tiles © OpenTopoMap (CC-BY-SA) · vector tiles OpenFreeMap · aerial imagery © basemap.at (CC BY 4.0)
Profile
The map, profile and gradient chart share one position — move your pointer over them and the marker follows. Colors are the gradient bands; the shaded span is the steepest 25 m. Any 25 m figure is good to about a point either way (why).
Measurement card
| Elevation | BEV ALS DTM 1 m — ALS DTM Höhenraster 1 m (Bundesamt für Eich- und Vermessungswesen with the Länder), EPSG:3035 |
|---|---|
| Resolution / CRS | 1.0 m grid, EPSG:3035; sampled every 1.0 m, bilinear interpolation |
| Tiles | E4322-N2680, E4323-N2680 |
| Road centreline | OpenStreetMap (local PBF extract) |
| Quality status | evidence quality B; caveated windows: canopy or structure, no bench excluded |
| Analysis | OCL 0.1.0, analysis 0.1.0, run at-run2-260911, calculated 2026-09-11 |
Provenance
{
"analysis_version": "0.1.0",
"sample_interval_m": 1.0,
"interpolation": "bilinear",
"smoothing": "none",
"gradient_windows_m": [
5.0,
10.0,
20.0,
25.0,
50.0,
100.0
],
"diagnostic_windows_m": [
2.0,
3.0
],
"elevation_crs": "EPSG:3035",
"elevation_resolution_m": 1.0,
"elevation_tiles": [
"data/cache/at/bev-als_dtm_E4322-N2680.tif",
"data/cache/at/bev-als_dtm_E4323-N2680.tif"
],
"calculated_at": "2026-09-11T15:55:06+00:00",
"road_source": "OpenStreetMap (local PBF extract)",
"road_attribution": "\u00a9 OpenStreetMap contributors, ODbL",
"osm_pbf_path": "data/cache/pbf/austria-2026-09-11-batch.osm.pbf",
"osm_snapshot": "",
"run_id": "at-run2-260911",
"elevation_provider": "BEV ALS DTM 1 m",
"elevation_licence": "Creative Commons Attribution 4.0 (CC BY 4.0) \u2014 \u00a9 BEV / L\u00e4nder, data.gv.at",
"elevation_dataset": "ALS DTM H\u00f6henraster 1 m (Bundesamt f\u00fcr Eich- und Vermessungswesen with the L\u00e4nder), EPSG:3035",
"elevation_tile_ids": [
"E4322-N2680",
"E4323-N2680"
],
"elevation_blocks": [
"N2650000E4300000@2022-09-15"
],
"climb_origin": "discovered",
"license": "ODbL-1.0",
"license_url": "https://howsteep.org/licensing"
}