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Merrymeet to Pengover Green°

2318.2 m · net rise 77.2 m · total ascent 130.9 m · overall 3.3% · confidence: good · Merrymeet · Cornwall

Shape: sustained — 40% of the climbing sits in a quarter of the distance; longest continuous stretch at 10%+ is 47 m.

Found purely from mapping and LiDAR data, and not yet matched against books, race records or lists — it may be well known to locals under a name we've never heard. It was cross-checked against the OS road network, surface models and map tags, but 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 you know this road, tell us what you found — photographs, corrections and local knowledge all welcome; the map links below let you scout it first.

° The name is provisional: this climb is not yet matched to a documented name, so it was named from nearby map places. There is no evidence of local usage — (auto-named from gazetteer (hypothesis, unreviewed); discovered as 'Discovered lane (50.4601, -4.4114)'). Corrections welcome.

≈ Overhead cover (tree canopy or structures) spans 10% 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?

WindowMaximumLocated at
2 m (diagnostic)47%1087–1089 munder overhead cover terrain reads 54.3% at 1534–1536 m across a structure — excluded
3 m (diagnostic)40%1128–1131 munder overhead cover terrain reads 48.3% at 1534–1537 m across a structure — excluded
5 m34%1127–1132 munder overhead cover terrain reads 35.3% at 1532–1537 m across a structure — excluded
10 m27%593–603 munder overhead cover
20 m23.0%525–545 m
25 m21.8%530–555 m
50 m17.7%526–576 m
100 m15.0%517–617 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

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

Merrymeet to Pengover Green LiDAR hillshade map with contours

Profile

Merrymeet to Pengover Green elevation profile Merrymeet to Pengover Green rolling gradient 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/england/bulk_dtm_1m/SX2560.tif",
    "data/cache/england/bulk_dtm_1m/SX2565.tif"
  ],
  "calculated_at": "2026-08-19T18:12:21+00:00",
  "road_source": "OpenStreetMap (local PBF extract)",
  "road_attribution": "\u00a9 OpenStreetMap contributors, ODbL",
  "osm_pbf_path": "data/cache/pbf/england-2026-08-12.osm.pbf",
  "osm_snapshot": "2026-08-12T20:21:46Z",
  "elevation_provider": "Environment Agency",
  "elevation_dataset": "EA LIDAR Composite DTM 1m (2022)",
  "elevation_licence": "Open Government Licence v3 \u2014 \u00a9 Environment Agency",
  "elevation_coverage_id": "13787b9a-26a4-4775-8523-806d13af58fc__Lidar_Composite_Elevation_DTM_1m",
  "elevation_tile_ids": [
    "SX2560.tif",
    "SX2565.tif"
  ],
  "climb_origin": "discovered",
  "notes": "Coarse pass: max 9.1% over 200 m (Terrain 50), gain 48.7 m over 1620 m way. EXTENDED by graph walk: +0 segment(s) at base, +3 at top (stop: base=no_descending_continuation, top=no_ascending_continuation; min_avg=2.0%). Review before adopting. ADOPTED (England launch slice 2026-08-16): clean-steep. AUTO-NAMED from gazetteer (hypothesis, unreviewed): was 'Discovered lane (50.4601, -4.4114)'.",
  "naming_note": "auto-named from gazetteer (hypothesis, unreviewed); discovered as 'Discovered lane (50.4601, -4.4114)'"
}