Penglais Hill
1309.8 m · gain 97.3 m · overall 7.4% · Buarth Mawr · Sir Ceredigion - Ceredigion
Shape: sustained — 33% of the climbing sits in a quarter of the distance; longest continuous stretch at 10%+ is 153 m.
Documented on the ground — sign: 11%. Signs get repainted and tags get retagged, so the date is part of the fact; on no cycling list we know of.
≈ 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) | ≈14.6% | 442–444 m | under overhead cover |
| 3 m (diagnostic) | 13.6% | 949–952 m | |
| 5 m | 12.8% | 951–956 m | |
| 10 m | 11.8% | 946–956 m | |
| 20 m | 11.2% | 1039–1059 m | |
| 25 m | 11.2% | 931–956 m | |
| 50 m | 10.9% | 921–971 m | |
| 100 m | 10.8% | 920–1020 m |
Map
Check this route yourself: Google Maps route via their router · Street View at the base where coverage exists · OSM way 4372117 highlights the mapped road · 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_23_259282_20220117dtm.tif",
"data/cache/wales/dtm_1m/wg_del_23_260281_20220117dtm.tif",
"data/cache/wales/dtm_1m/wg_del_23_260282_20220117dtm.tif",
"data/cache/wales/dtm_1m/wg_del_29_258281_20220319dtm.tif",
"data/cache/wales/dtm_1m/wg_del_29_258282_20220319dtm.tif",
"data/cache/wales/dtm_1m/wg_del_29_259281_20220319dtm.tif"
],
"calculated_at": "2026-08-12T14:32:38+00:00",
"road_source": "OpenStreetMap (local PBF extract)",
"road_attribution": "\u00a9 OpenStreetMap contributors, ODbL",
"osm_ids": [
4372117,
1482220365,
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],
"osm_versions": {
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"1482220365": 3,
"1482220364": 3,
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"217282207": 15,
"1482220354": 2,
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"379924480": 6,
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"1482226160": 1,
"215493458": 8,
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},
"osm_timestamps": {
"4372117": "2026-03-06 07:55:31+00:00",
"1482220365": "2026-03-06 07:53:56+00:00",
"1482220364": "2026-03-06 07:53:32+00:00",
"1482220363": "2026-03-06 07:53:29+00:00",
"1482220362": "2026-03-06 07:53:09+00:00",
"1482220361": "2026-03-06 07:52:49+00:00",
"1482220360": "2026-03-06 07:52:48+00:00",
"1482220359": "2026-02-24 19:35:14+00:00",
"1482220356": "2026-02-24 19:35:14+00:00",
"217282207": "2026-02-24 19:35:14+00:00",
"1482220354": "2026-02-23 13:51:02+00:00",
"1482220355": "2026-02-23 13:51:02+00:00",
"1482226159": "2026-02-23 13:51:02+00:00",
"162780795": "2026-02-23 13:51:02+00:00",
"379924480": "2026-02-23 13:51:02+00:00",
"261063475": "2026-02-23 13:51:02+00:00",
"1482226160": "2026-02-23 13:51:02+00:00",
"215493458": "2026-02-23 13:51:02+00:00",
"380895373": "2026-02-23 13:51:02+00:00"
},
"osm_retrieved_at": "2026-08-12T14:32:38+00:00",
"osm_pbf_path": "data/cache/pbf/wales-2026-08-11.osm.pbf",
"osm_snapshot": "2026-08-10T20:21:40Z",
"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_23_259282_20220117dtm.tif",
"wg_del_23_260281_20220117dtm.tif",
"wg_del_23_260282_20220117dtm.tif",
"wg_del_29_258281_20220319dtm.tif",
"wg_del_29_258282_20220319dtm.tif",
"wg_del_29_259281_20220319dtm.tif"
],
"elevation_capture_dates": [
"17-01-2022",
"19-03-2022"
],
"climb_origin": "named",
"signed_gradient_pct": 11,
"signed_source": "Road sign / OSM incline tag (11%) carried by the whole Penglais Road way chain"
}