Park Street
995.8 m · gain 76.0 m · overall 7.6% · Cwm Clydach · Rhondda Cynon Taf
Shape: stepped — 49% of the climbing sits in a quarter of the distance; longest continuous stretch at 10%+ is 80 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.
Gradient ladder what do windows mean?
| Window | Maximum | Located at | |
|---|---|---|---|
| 2 m (diagnostic) | 25.1% | 791–793 m | |
| 3 m (diagnostic) | 24.6% | 791–794 m | |
| 5 m | 24.2% | 811–816 m | |
| 10 m | 23.8% | 811–821 m | |
| 20 m | 23.2% | 777–797 m | |
| 25 m | 23.0% | 773–798 m | |
| 50 m | 22.4% | 772–822 m | |
| 100 m | 20.2% | 767–867 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
© 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_5_297192_20201224dtm.tif",
"data/cache/wales/dtm_1m/wg_del_5_297193_20201224dtm.tif"
],
"calculated_at": "2026-08-12T09:11:06+00:00",
"road_source": "OpenStreetMap (local PBF extract)",
"road_attribution": "\u00a9 OpenStreetMap contributors, ODbL",
"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_5_297192_20201224dtm.tif",
"wg_del_5_297193_20201224dtm.tif"
],
"elevation_capture_dates": [
"24-12-2020"
],
"climb_origin": "discovered",
"notes": "Coarse pass: max 8.1% over 200 m (Terrain 50), gain 43.1 m over 694 m way. EXTENDED by graph walk: +0 segment(s) at base, +6 at top (stop: base=no_descending_continuation, top=no_ascending_continuation; min_avg=2.0%). Review before adopting. ROAD-REVIEW: way 747676353: unnamed service way; way 747676353: service way, surface untagged; way 850479450: unnamed service way; way 850479450: service way, surface untagged ADOPTED (notable slice 2026-08-11): clean-steep."
}