Blacksmill Hill to Clockmill°
3508.0 m · net rise 190.0 m · total ascent 191.8 m · overall 5.4% · confidence: good · Hell's Cleugh · Scottish Borders
Shape: sustained — 44% of the climbing sits in a quarter of the distance; longest continuous stretch at 10%+ is 97 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 (55.7793, -2.4143)'). Corrections welcome.
≈ Overhead cover (tree canopy or structures) spans 8% 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) | ≈15% | 2119–2121 m | under overhead cover |
| 3 m (diagnostic) | 14% | 2119–2122 m | |
| 5 m | ≈14% | 2119–2124 m | under overhead cover |
| 10 m | ≈13% | 2117–2127 m | under overhead cover |
| 20 m | ≈12.5% | 2111–2131 m | under overhead cover |
| 25 m | ≈12.3% | 2111–2136 m | under overhead cover |
| 50 m | 11.5% | 1655–1705 m | |
| 100 m | 11.0% | 2293–2393 m |
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/NT75SW.tif",
"data/cache/scotland/phase-3/dtm/NT75SE.tif"
],
"calculated_at": "2026-08-18T18:40:50+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": [
"NT75SW",
"NT75SE"
],
"route_summit_trim_m": 1207.9,
"route_summit_trim_loss_m": 30.7,
"climb_origin": "discovered",
"notes": "Coarse pass: max 12.8% over 200 m (Terrain 50), gain 158.2 m over 4716 m way. KEPT at seed extent: no ascending continuation (min_avg=2.0%). ADOPTED (Scotland launch 2026-08-18): big-gain. AUTO-NAMED from gazetteer (hypothesis, unreviewed): was 'Discovered lane (55.7793, -2.4143)'.",
"naming_note": "auto-named from gazetteer (hypothesis, unreviewed); discovered as 'Discovered lane (55.7793, -2.4143)'"
}