Crimea Pass (Bwlch y Gorddinan)
2704.9 m · net rise 260.1 m · total ascent 262.2 m · overall 9.6% · confidence: needs confirmation · Tal-y-waenydd · Gwynedd
Shape: sustained — 33% of the climbing sits in a quarter of the distance; longest continuous stretch at 10%+ is 525 m.
Matches: Wikipedia, Simon Warren 100 Climbs app (Wales collections) — Crimea Pass (Bwlch y Gorddinan) — articles in English and Welsh — Crimea Pass — listed unnumbered; Wales-volume/X-List attribution to confirm in-app.
needs review short_window_divergence — treat short-window maxima here as provisional.
Gradient ladder what do windows mean?
| Window | Maximum | Located at | |
|---|---|---|---|
| 2 m (diagnostic) | ≈39% | 30–32 m | under overhead cover terrain reads 122.0% at 21–23 m across a structure — excluded |
| 3 m (diagnostic) | ≈38% | 29–32 m | under overhead cover terrain reads 122.0% at 21–24 m across a structure — excluded |
| 5 m | ≈35% | 28–33 m | under overhead cover terrain reads 111.5% at 20–25 m across a structure — excluded |
| 10 m | ≈26% | 28–38 m | under overhead cover terrain reads 73.6% at 19–29 m across a structure — excluded |
| 20 m | ≈19.3% | 1912–1932 m | under overhead cover terrain reads 48.6% at 19–39 m across a structure — excluded |
| 25 m | ≈18.4% | 1907–1932 m | under overhead cover terrain reads 40.0% at 19–44 m across a structure — excluded |
| 50 m | ≈17.7% | 2036–2086 m | under overhead cover terrain reads 23.4% at 19–69 m across a structure — excluded |
| 100 m | 17.2% | 1997–2097 m |
may_start_earlier 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.
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
{
"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_17_269348_20210330dtm.tif",
"data/cache/wales/dtm_1m/wg_del_17_270348_20210330dtm.tif",
"data/cache/wales/dtm_1m/wg_del_20_269346_20220111dtm.tif",
"data/cache/wales/dtm_1m/wg_del_20_269347_20220111dtm.tif",
"data/cache/wales/dtm_1m/wg_del_20_270346_20220111dtm.tif",
"data/cache/wales/dtm_1m/wg_del_20_270347_20220111dtm.tif"
],
"calculated_at": "2026-08-12T23:12:05+00:00",
"road_source": "trunk-adopted-routes/discovered-lane-53-0055-3-9425.geojson",
"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_17_269348_20210330dtm.tif",
"wg_del_17_270348_20210330dtm.tif",
"wg_del_20_269346_20220111dtm.tif",
"wg_del_20_269347_20220111dtm.tif",
"wg_del_20_270346_20220111dtm.tif",
"wg_del_20_270347_20220111dtm.tif"
],
"elevation_capture_dates": [
"11-01-2022",
"30-03-2021"
],
"climb_origin": "discovered",
"notes": "Coarse pass: max 12.7% over 200 m (Terrain 50), gain 52.5 m over 517 m way. EXTENDED by graph walk: +0 segment(s) at base, +8 at top (stop: base=no_descending_continuation, top=no_ascending_continuation; min_avg=2.0%). Review before adopting. ADOPTED (window-flag adjudication, Peter's Street View verdict 2026-08-12): long steady grade, no crossing structures \u2014 the 2-25 m window flags are DTM artifacts on a real climb; see road-review-verdicts.yaml. NAMED by human review. Absorbs discovered-lane-53-0154-3-9441 (95% route containment) and twin seed discovered-lane-53-0105-3-9451 (identical chain)."
}