BETA — measurements and names under active refinement. Seen a sign, a gate, or a better name? Submit an update no account needed · photos welcome via GitHub

Lane near Cwrt

1015.4 m · net rise 93.9 m · total ascent 96.2 m · overall 9.2% · confidence: high · Cwrt · Gwynedd · share

Shape: sustained — 34% of the climbing sits in a quarter of the distance; longest continuous stretch at 10%+ is 144 m.

Documented on the ground — tag: 20% (2026). 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 26% 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)	40%	956–958 m
3 m (diagnostic)	40%	956–959 m
5 m	37%	955–960 m
10 m	31%	951–961 m
20 m	25.6%	950–970 m
25 m	24.4%	948–973 m
50 m	20.0%	935–985 m
100 m	17.5%	874–974 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.

Measured, not vetted. This page records what the laser record shows about the road's shape — nothing more. Nobody has necessarily ridden or inspected this road for the survey, and a page here is not a recommendation and no guarantee that the road is open, surfaced, rideable or safe. Gates, private sections, missing rights of way and hazards do not show up in elevation data. Check access and conditions on the ground and make your own judgment.

Ridden it, or know better? Submit data for this climb no account needed · Share this climb

Lane near Cwrt 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_22_266299_20220114dtm.tif",
    "data/cache/wales/dtm_1m/wg_del_22_267299_20220114dtm.tif"
  ],
  "calculated_at": "2026-08-12T09:12:08+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_22_266299_20220114dtm.tif",
    "wg_del_22_267299_20220114dtm.tif"
  ],
  "elevation_capture_dates": [
    "14-01-2022"
  ],
  "climb_origin": "osm_incline",
  "notes": "Promoted automatically from triage verdict=validated. Named from nearest OSM place node (Cwrt); originally unnamed at (52.5795, -3.966). EXTENDED by graph walk: +2 segment(s) at base, +0 at top (stop: base=no_descending_continuation, top=no_ascending_continuation; min_avg=2.0%). Review before adopting.",
  "license": "ODbL-1.0",
  "license_url": "https://howsteep.org/licensing.html"
}