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Gravel / dirt track · listed, not ranked

1302.4 m · net rise 78.1 m · total ascent 84.8 m · overall 6.0% · evidence quality B (good) · Périgueux · Dordogne

Shape: sustained — 36% of the climbing sits in a quarter of the distance; longest continuous stretch at 10%+ is 62 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 IGN’s BD TOPO® road network, OpenStreetMap and the classified LiDAR HD point cloud, 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.

≈ Overhead cover (tree canopy or structures) spans 78% 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.

Lane near Moulin Neuf (Périgueux, Dordogne) is 1302.4 m long at 6.0% overall; its steepest 25 m averages ≈16.0% and its steepest 100 m ≈8.0%, measured from IGN's LiDAR HD 0.5 m laser surveys along the mapped road centreline.

Gradient ladder what do windows mean?

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: unpaved (97% unpaved), according to BD TOPO®, IGN's national topographic database: paved for the first 20 m; surface unrecorded for the first 467 m; unpaved from 467 m to 1,165 m; off the road model from 1,165 m to the top.

Pending human review: the steepest stretch of this climb (1223–1248 m) looks like a track rather than a made road: the way under it is mapped as a driveway, which is private access (about 100% of the steepest 25 m and 0% of the line). The figure is published as measured and has not been adjusted, but a climb whose steepest stretch looks like a track is listed, not ranked, until a person has looked.

Access: Listed 2026-09-27 (inventory hunt wave 1): road audit — way 221372050: unnamed service way; way 221372050: service way, surface untagged. Never silently ranked or dropped.

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 © IGN, BD ORTHO® (Licence Ouverte Etalab 2.0)

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

Provenance

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