Collin to Carthat Hill°
3707.5 m · net rise 195.7 m · total ascent 242.3 m · overall 5.3% · confidence: good · Woodside · Dumfries and Galloway
Shape: sustained — 33% of the climbing sits in a quarter of the distance; longest continuous stretch at 10%+ is 91 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 OS road network, surface models and map tags, 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.
° The name is provisional: this climb is not yet matched to a documented name, so it was named from nearby map places. There is no evidence of local usage — (auto-named from gazetteer (hypothesis, unreviewed); discovered as 'Discovered lane (55.0771, -3.4952)'). Corrections welcome.
≈ Overhead cover (tree canopy or structures) spans 11% 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.
Gradient ladder what do windows mean?
| Window | Maximum | Located at | |
|---|---|---|---|
| 2 m (diagnostic) | ≈39% | 1073–1075 m | under overhead cover |
| 3 m (diagnostic) | 31% | 1072–1075 m | |
| 5 m | 26% | 1008–1013 m | |
| 10 m | 22% | 1003–1013 m | |
| 20 m | 17.0% | 2061–2081 m | |
| 25 m | 16.1% | 2056–2081 m | |
| 50 m | 14.7% | 2033–2083 m | |
| 100 m | ≈12.4% | 2814–2914 m | under overhead cover |
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.
Ridden it, or know better? Submit data for this climb no account needed
© OpenStreetMap contributors · topo tiles © OpenTopoMap (CC-BY-SA) · vector tiles OpenFreeMap

Profile
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:27700",
"elevation_resolution_m": 0.5,
"elevation_tiles": [
"data/cache/scotland/phase-3/dtm/NY07NW.tif",
"data/cache/scotland/phase-3/dtm/NY07NE.tif"
],
"calculated_at": "2026-08-18T18:37:34+00:00",
"road_source": "OpenStreetMap (local PBF extract)",
"road_attribution": "\u00a9 OpenStreetMap contributors, ODbL",
"osm_pbf_path": "data/cache/pbf/scotland-2026-08-14-roads.osm.pbf",
"osm_snapshot": "2026-08-13T20:21:01Z",
"elevation_provider": "Scottish Remote Sensing Portal (AWS Open Data, srsp-open-data)",
"elevation_licence": "Open Government Licence v3 \u2014 \u00a9 Scottish Government, SEPA and partners; Crown copyright",
"elevation_dataset": "Scottish Public Sector LiDAR Phase 3 50cm",
"elevation_tile_ids": [
"NY07NW",
"NY07NE"
],
"climb_origin": "discovered",
"notes": "Coarse pass: max 10.7% over 200 m (Terrain 50), gain 192.7 m over 3599 m way. EXTENDED by graph walk: +2 segment(s) at base, +0 at top (stop: base=no_descending_continuation, top=no_ascending_continuation; min_avg=2.0%). Review before adopting. ADOPTED (Scotland launch 2026-08-18): big-gain. AUTO-NAMED from gazetteer (hypothesis, unreviewed): was 'Discovered lane (55.0771, -3.4952)'.",
"naming_note": "auto-named from gazetteer (hypothesis, unreviewed); discovered as 'Discovered lane (55.0771, -3.4952)'"
}