BETA — measurements and names under active refinement. Seen a sign, a gate, or a better name? Report it (photos welcome).

Primrose Hill

309.6 m · gain 27.9 m · overall 9.0% · Pwllhobi · Sir Ceredigion - Ceredigion

Shape: sustained — 36% of the climbing sits in a quarter of the distance; longest continuous stretch at 10%+ is 94 m.

Documented on the ground — tag: 12% (2026). Signs get repainted and tags get retagged, so the date is part of the fact; on no cycling list we know of.

Gradient ladder what do windows mean?

Window	Maximum	Located at
2 m (diagnostic)	18.0%	283–285 m
3 m (diagnostic)	16.4%	291–294 m
5 m	15.8%	299–304 m
10 m	15.3%	291–301 m
20 m	15.0%	283–303 m
25 m	14.7%	283–308 m
50 m	13.4%	142–192 m
100 m	12.3%	109–209 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 · OSM way 379919473 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.

Primrose Hill LiDAR hillshade map with contours

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_260280_20220117dtm.tif",
    "data/cache/wales/dtm_1m/wg_del_23_260281_20220117dtm.tif",
    "data/cache/wales/dtm_1m/wg_del_29_259280_20220319dtm.tif",
    "data/cache/wales/dtm_1m/wg_del_29_259281_20220319dtm.tif"
  ],
  "calculated_at": "2026-08-12T14:32:39+00:00",
  "road_source": "OpenStreetMap (local PBF extract)",
  "road_attribution": "\u00a9 OpenStreetMap contributors, ODbL",
  "osm_ids": [
    379919473,
    219140741,
    68543978
  ],
  "osm_versions": {
    "379919473": 3,
    "219140741": 8,
    "68543978": 11
  },
  "osm_timestamps": {
    "379919473": "2025-03-24 07:32:18+00:00",
    "219140741": "2026-01-28 20:50:33+00:00",
    "68543978": "2026-03-11 04:39:45+00:00"
  },
  "osm_retrieved_at": "2026-08-12T14:32:39+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_260280_20220117dtm.tif",
    "wg_del_23_260281_20220117dtm.tif",
    "wg_del_29_259280_20220319dtm.tif",
    "wg_del_29_259281_20220319dtm.tif"
  ],
  "elevation_capture_dates": [
    "17-01-2022",
    "19-03-2022"
  ],
  "climb_origin": "named",
  "signed_gradient_pct": 12,
  "signed_source": "OSM incline tag (12%) on the upper way"
}