Lane near Glyn Saer°
7042.7 m · gain 149.8 m · overall 2.1% · Cwm-bychan · Sir Gaerfyrddin - Carmarthenshire
Shape: stepped — 48% of the climbing sits in a quarter of the distance; longest continuous stretch at 10%+ is 31 m.
An unlisted find of this survey, on no list we know of. It was discovered by analysing LiDAR terrain data and cross-checked against the OS road network, surface models and map tags — but despite all that, 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 that someone is you, 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 appears on no list we know of, 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 (52.0725, -3.6991)'). Corrections welcome.
needs review short_window_divergence — treat short-window maxima here as provisional.
≈ Overhead cover (tree canopy or structures) spans 7% 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, not wrong. Longer windows average over more clean ground and are steadier.
Gradient ladder what do windows mean?
| Window | Maximum | Located at | |
|---|---|---|---|
| 2 m (diagnostic) | 38.2% | 5782–5784 m | |
| 3 m (diagnostic) | 38.2% | 5781–5784 m | |
| 5 m | 35.0% | 5780–5785 m | |
| 10 m | 19.0% | 5779–5789 m | |
| 20 m | 12.6% | 7022–7042 m | |
| 25 m | 11.7% | 7017–7042 m | |
| 50 m | 10.0% | 6240–6290 m | |
| 100 m | 9.0% | 6237–6337 m |
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.
© 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": 1.0,
"elevation_tiles": [
"data/cache/wales/dtm_1m/wg_del_28_282241_20220316dtm.tif",
"data/cache/wales/dtm_1m/wg_del_28_282242_20220316dtm.tif",
"data/cache/wales/dtm_1m/wg_del_28_282243_20220316dtm.tif",
"data/cache/wales/dtm_1m/wg_del_28_282244_20220316dtm.tif",
"data/cache/wales/dtm_1m/wg_del_28_282245_20220316dtm.tif",
"data/cache/wales/dtm_1m/wg_del_28_283241_20220316dtm.tif",
"data/cache/wales/dtm_1m/wg_del_28_283242_20220316dtm.tif",
"data/cache/wales/dtm_1m/wg_del_28_283245_20220316dtm.tif",
"data/cache/wales/dtm_1m/wg_del_28_284241_20220316dtm.tif",
"data/cache/wales/dtm_1m/wg_del_28_284242_20220316dtm.tif",
"data/cache/wales/dtm_1m/wg_del_28_284245_20220316dtm.tif",
"data/cache/wales/dtm_1m/wg_del_28_285241_20220316dtm.tif",
"data/cache/wales/dtm_1m/wg_del_28_285242_20220316dtm.tif",
"data/cache/wales/dtm_1m/wg_del_28_285243_20220316dtm.tif",
"data/cache/wales/dtm_1m/wg_del_28_285245_20220316dtm.tif",
"data/cache/wales/dtm_1m/wg_del_28_286241_20220316dtm.tif",
"data/cache/wales/dtm_1m/wg_del_28_286242_20220316dtm.tif",
"data/cache/wales/dtm_1m/wg_del_28_286243_20220316dtm.tif",
"data/cache/wales/dtm_1m/wg_del_28_286244_20220316dtm.tif",
"data/cache/wales/dtm_1m/wg_del_28_286245_20220316dtm.tif",
"data/cache/wales/dtm_1m/wg_del_30_283243_20220323dtm.tif",
"data/cache/wales/dtm_1m/wg_del_30_283244_20220323dtm.tif",
"data/cache/wales/dtm_1m/wg_del_30_284243_20220323dtm.tif",
"data/cache/wales/dtm_1m/wg_del_30_284244_20220323dtm.tif",
"data/cache/wales/dtm_1m/wg_del_30_285244_20220323dtm.tif"
],
"calculated_at": "2026-08-12T23:12:16+00:00",
"road_source": "trunk-adopted-routes/discovered-lane-52-0725-3-6991.geojson",
"elevation_provider": "Welsh Government",
"elevation_dataset": "Welsh Government LiDAR 1m DTM (2020-2023)",
"elevation_licence": "Open Government Licence v3 \u2014 \u00a9 Crown copyright Welsh Government",
"elevation_catalogue_layer": "geonode:welsh_government_lidar_tile_catalogue_2020_2023",
"elevation_tile_ids": [
"wg_del_28_282241_20220316dtm.tif",
"wg_del_28_282242_20220316dtm.tif",
"wg_del_28_282243_20220316dtm.tif",
"wg_del_28_282244_20220316dtm.tif",
"wg_del_28_282245_20220316dtm.tif",
"wg_del_28_283241_20220316dtm.tif",
"wg_del_28_283242_20220316dtm.tif",
"wg_del_28_283245_20220316dtm.tif",
"wg_del_28_284241_20220316dtm.tif",
"wg_del_28_284242_20220316dtm.tif",
"wg_del_28_284245_20220316dtm.tif",
"wg_del_28_285241_20220316dtm.tif",
"wg_del_28_285242_20220316dtm.tif",
"wg_del_28_285243_20220316dtm.tif",
"wg_del_28_285245_20220316dtm.tif",
"wg_del_28_286241_20220316dtm.tif",
"wg_del_28_286242_20220316dtm.tif",
"wg_del_28_286243_20220316dtm.tif",
"wg_del_28_286244_20220316dtm.tif",
"wg_del_28_286245_20220316dtm.tif",
"wg_del_30_283243_20220323dtm.tif",
"wg_del_30_283244_20220323dtm.tif",
"wg_del_30_284243_20220323dtm.tif",
"wg_del_30_284244_20220323dtm.tif",
"wg_del_30_285244_20220323dtm.tif"
],
"elevation_capture_dates": [
"17-03-2022"
],
"climb_origin": "discovered",
"notes": "Coarse pass: max 8.6% over 200 m (Terrain 50), gain 84.7 m over 5782 m way. EXTENDED by graph walk: +2 segment(s) at base, +3 at top (stop: base=no_descending_continuation, top=no_ascending_continuation; min_avg=2.0%). Review before adopting. ADOPTED (trunk sweep, Peter's on-sight verdict 2026-08-12): clean table, adopt-all. AUTO-NAMED from gazetteer (hypothesis, unreviewed): was 'Discovered lane (52.0725, -3.6991)'.",
"naming_note": "auto-named from gazetteer (hypothesis, unreviewed); discovered as 'Discovered lane (52.0725, -3.6991)'"
}