Penglais Hill
1309.8 m · net rise 97.3 m · overall 7.4% · confidence: high · Buarth Mawr · 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% (2026, via OSM). Signs get repainted and tags get retagged, so the date is part of the fact; not yet matched against any cycling list.
≈ 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 — 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% | 442–444 m | under overhead cover |
| 3 m (diagnostic) | 14% | 949–952 m | |
| 5 m | 13% | 951–956 m | |
| 10 m | 12% | 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 |
≈ appears only on the 2–3 m diagnostic rows here, which does not lower the confidence letter: those windows are never headline values or ranking keys, so confidence reflects the standard (5–100 m) windows — which are clean on this climb.
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.
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
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"interpolation": "bilinear",
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],
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}