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Col de Salèse from Mollières

Gravel / dirt track · listed, not ranked

6670.8 m · net rise 461.6 m · total ascent 487.0 m · overall 6.9% · evidence quality B (good) · Valdeblore · Alpes-Maritimes

Shape: sustained — 28% of the climbing sits in a quarter of the distance; longest continuous stretch at 10%+ is 38 m.

Not yet matched against documented climbs — the measurement stands on its own.

≈ Overhead cover (tree canopy or structures) spans 17% of this route — detected by comparing the surface model (DSM, treetops and rooftops) against the terrain model (DTM, bare ground). Under cover the bare-ground model is built from fewer laser returns, so metre-scale readings can wobble; maxima whose window sits in a covered zone are marked ≈ below — less certain — the flag does not say whether the true value is higher or lower. Longer windows average over more clean ground and are steadier.

Col de Salèse from Mollières (Valdeblore, Alpes-Maritimes) is 6670.8 m long at 6.9% overall; its steepest 25 m averages ≈19.1% and its steepest 100 m ≈9.8%, measured from IGN's LiDAR HD 0.5 m laser surveys along the mapped road centreline.

Gradient ladder what do windows mean?

WindowMaximumLocated at
2 m (diagnostic)≈32%200–202 munder overhead cover terrain reads 158.2% at 681–683 m across a structure — excluded
3 m (diagnostic)≈26%215–218 munder overhead cover terrain reads 133.9% at 681–684 m across a structure — excluded
5 m≈23%2256–2261 munder overhead cover terrain reads 85.7% at 680–685 m across a structure — excluded
10 m≈21%2251–2261 munder overhead cover terrain reads 44.9% at 680–690 m across a structure — excluded
20 m≈20.5%2241–2261 munder overhead cover terrain reads 24.3% at 680–700 m across a structure — excluded
25 m≈19.1%2239–2264 munder overhead cover terrain reads 20.2% at 680–705 m across a structure — excluded
50 m14.0%2230–2280 m
100 m≈9.8%2224–2324 munder overhead cover terrain reads 10.4% at 680–780 m across a structure — excluded

descends at start 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: unpaved (92% unpaved), according to BD TOPO®, IGN's national topographic database: paved for the first 110 m; unpaved from 110 m to 6,258 m; paved from 6,258 m to the top. The steepest 25 m lies on the unpaved part.

Access: Listed, not ranked (restricted-access-window): the road authority records this road as restricted to authorised users (for example 'restreint aux ayants droit') over most of the route, including the steepest 25 m. The page stays for the record and the climb is published as measured; a road the public may not drive is not ranked. Check access on the ground.

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 ·

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.

  © OpenStreetMap contributors · topo tiles © OpenTopoMap (CC-BY-SA) · vector tiles OpenFreeMap · aerial imagery © IGN, BD ORTHO® (Licence Ouverte Etalab 2.0)

Col de Salèse from Mollières LiDAR hillshade map with contours

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).

Col de Salèse from Mollières elevation profile
Col de Salèse from Mollières rolling gradient profile
 

Measurement card

ElevationIGN LiDAR HD MNT 0.5 m — LiDAR HD — MNT (sol) et MNS (surface), 0,50 m (Institut national de l'information géographique et forestière), RGF93 / Lambert-93 EPSG:2154, altitudes IGN69
Resolution / CRS0.5 m grid, EPSG:2154; sampled every 1.0 m, bilinear interpolation
TilesE1033-N6348, E1034-N6347, E1034-N6348, E1035-N6346, E1035-N6347, E1035-N6348, E1036-N6346, E1036-N6347, E1037-N6346, E1037-N6347, E1038-N6346, E1038-N6347
Road centrelineOpenStreetMap (local PBF extract)
Quality statusevidence quality B; caveated windows: canopy or structure, structure excluded, structure excluded min, suppression carried, texture excluded
AnalysisOCL 0.1.0, analysis 0.1.0, run remeasure-260929c-fr, calculated 2026-09-29

Provenance

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    "elevation_provider_key": "ign-lidarhd",
    "tile_index": "wms-grid",
    "authority": "bdtopo",
    "registry_pbf": "france-vosges-2026-09-16.osm.pbf",
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  "elevation_crs": "EPSG:2154",
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  "calculated_at": "2026-09-29T14:52:27+00:00",
  "road_source": "OpenStreetMap (local PBF extract)",
  "road_attribution": "\u00a9 OpenStreetMap contributors, ODbL",
  "osm_pbf_path": "output/remeasure-260929c-alpsN/fr/batch-france-chunk001.pbf",
  "osm_snapshot": "",
  "run_id": "remeasure-260929c-fr",
  "elevation_provider": "IGN LiDAR HD MNT 0.5 m",
  "elevation_licence": "Licence Ouverte / Open Licence 2.0 (Etalab) \u2014 \u00a9 IGN, LiDAR HD (MNT/MNS), data.geopf.fr; reproduction autoris\u00e9e avec mention de la source et de la date",
  "elevation_dataset": "LiDAR HD \u2014 MNT (sol) et MNS (surface), 0,50 m (Institut national de l'information g\u00e9ographique et foresti\u00e8re), RGF93 / Lambert-93 EPSG:2154, altitudes IGN69",
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  "elevation_blocks": [
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    "LHD_FXX_1034_6349_MNT_O_0M50_LAMB93_IGN69": "2025-04-02",
    "LHD_FXX_1035_6347_MNT_O_0M50_LAMB93_IGN69": "2025-04-02",
    "LHD_FXX_1035_6348_MNT_O_0M50_LAMB93_IGN69": "2025-04-02",
    "LHD_FXX_1035_6349_MNT_O_0M50_LAMB93_IGN69": "2025-04-02",
    "LHD_FXX_1036_6347_MNT_O_0M50_LAMB93_IGN69": "2025-06-20",
    "LHD_FXX_1036_6348_MNT_O_0M50_LAMB93_IGN69": "2025-06-20",
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  },
  "climb_origin": "named-pass",
  "access_overrides": [
    "motor_vehicle=private"
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  "seam_filled_samples": {
    "count": 0,
    "distances_m": []
  },
  "seam_filled_in_maximum": false,
  "structure_own_ways": 6,
  "structure_own_ways_source": "map-matched to the road network: the entry carried no way list, so the ways the route runs along were found by geometry (ukclimb.batch.own_ways_by_geometry)",
  "structure_mask_ranges_m": [
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      3403.5
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  ],
  "prior_doc": {
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    "calculated_at": "2026-09-18T06:17:12+00:00",
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    "spans": 8,
    "sources": [
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  "suppression_carried": [
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      "published_reason": "short-step",
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    "single_track_rule": "PROVISIONAL (2026-09-15): width_p10_m <= 3.0 m with bounded_share >= 0.6; recorded, not a rule",
    "status": "ok",
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  "remeasured": {
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    "why": "block-extract cache sweep: fold the fallers, risers held published (standing rulings)",
    "published_max25_pct": 19.18,
    "max25_pct": 19.15
  },
  "license": "ODbL-1.0",
  "license_url": "https://howsteep.org/licensing"
}