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Paved · listed, not ranked

917.7 m · net rise 102.1 m · total ascent 121.2 m · overall 11.1% · evidence quality B (good) · Muntogna da Schons · Graubünden/Grischun/Grigioni

Shape: sustained — 36% of the climbing sits in a quarter of the distance; longest continuous stretch at 10%+ is 353 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 swisstopo’s swissTLM3D road model, 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.

Veia Muntogna da Schons (Muntogna da Schons, Graubünden/Grischun/Grigioni) is 917.7 m long at 11.1% overall; its steepest 25 m averages ≈16.0% and its steepest 100 m ≈15.6%, measured from swisstopo's swissALTI3D 0.5 m LiDAR along the mapped road centreline.

Gradient ladder what do windows mean?

may start earlier 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: paved throughout, according to swisstopo's swissTLM3D road model.

Access: Listed 2026-09-15 (re-measured on the trimmed extent): with the tail dog-leg cut off (a driveway, the ruling of 2026-09-15), the steepest 25 m reads 16.0 % on the 918 m public extent (re-measured 2026-10-31, still trimmed at that bend), below the ranking door — kept as a listed page.

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

Load the interactive map

Route colour = gradient over a 25 m window: <10% 10–20% 20–25% ≥25%

Route line = the road surface as the LiDAR survey finds it. Basemap roads are for orientation and may sit a few metres off.

Topo (contours) Vector Aerial   © OpenStreetMap contributors · topo tiles © OpenTopoMap (CC-BY-SA) · vector tiles OpenFreeMap · aerial imagery © swisstopo

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

Provenance

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    "analysis_config_digest": "sha256:cadd8ced0d561e22",
    "python": "3.12.12",
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    "region_key": "switzerland",
    "crs": "EPSG:2056",
    "elevation_provider_key": "swisstopo",
    "tile_index": "stac",
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    "registry_pbf": "switzerland-2026-09-10.osm.pbf",
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  "sample_interval_m": 1.0,
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  "elevation_crs": "EPSG:2056",
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  "elevation_tiles": [
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  ],
  "calculated_at": "2026-10-31T02:00:37+00:00",
  "road_source": "OpenStreetMap (local PBF extract)",
  "road_attribution": "\u00a9 OpenStreetMap contributors, ODbL",
  "osm_pbf_path": "data/cache/pbf/switzerland-2026-09-10-batch.osm.pbf",
  "osm_snapshot": "",
  "run_id": "p4-chfr-residue-261030",
  "elevation_provider": "swisstopo swissALTI3D",
  "elevation_licence": "swisstopo open government data (OGD): free use, attribution '\u00a9 swisstopo' \u2014 https://www.swisstopo.admin.ch/en/terms-and-conditions",
  "elevation_dataset": "swissALTI3D 0.5 m DTM (Federal Office of Topography swisstopo)",
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  },
  "route_cut_m": 917.7,
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  "seam_filled_samples": {
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  "canopy_check": "unavailable \u2014 no surface model (DSM or point cloud) registered for this coverage",
  "structure_own_ways": 8,
  "tunnel_check": "osm tunnel=* ways on 8 own way(s)",
  "tunnel_ranges_m": [],
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    "hedge_to_hedge": {
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  },
  "remeasured": {
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