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Milladon Lane

335.1 m · net rise 52.6 m · total ascent 53.4 m · overall 15.7% · confidence: needs confirmation · Bake Bottoms · Cornwall

Shape: sustained — 33% of the climbing sits in a quarter of the distance; longest continuous stretch at 10%+ is 185 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.

needs review short_window_divergence — treat short-window maxima here as provisional.

≈ 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)52%142–144 munder overhead cover terrain reads 56.2% at 325–327 m across a structure — excluded
3 m (diagnostic)50%142–145 munder overhead cover terrain reads 54.2% at 325–328 m across a structure — excluded
5 m40%140–145 munder overhead cover terrain reads 47.7% at 324–329 m across a structure — excluded
10 m32%138–148 munder overhead cover terrain reads 39.9% at 323–333 m across a structure — excluded
20 m26.3%129–149 munder overhead cover terrain reads 28.2% at 314–334 m across a structure — excluded
25 m24.8%123–148 munder overhead cover terrain reads 25.7% at 309–334 m across a structure — excluded
50 m21.6%99–149 m
100 m19.9%99–199 m

may_start_earliermay_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.

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

  © OpenStreetMap contributors · topo tiles © OpenTopoMap (CC-BY-SA) · vector tiles OpenFreeMap

Milladon Lane LiDAR hillshade map with contours

Profile

Milladon Lane elevation profile Milladon Lane 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/SX3055.tif"
  ],
  "calculated_at": "2026-08-15T00:15:38+00:00",
  "road_source": "OpenStreetMap (local PBF extract)",
  "road_attribution": "\u00a9 OpenStreetMap contributors, ODbL",
  "osm_pbf_path": "data/cache/pbf/england-2026-08-12-roads.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": [
    "SX3055.tif"
  ],
  "climb_origin": "discovered",
  "notes": "Coarse pass: max 15.9% over 200 m (Terrain 50), gain 32.5 m over 205 m way. EXTENDED by graph walk: +0 segment(s) at base, +1 at top (stop: base=no_descending_continuation, top=no_ascending_continuation; min_avg=2.0%). Review before adopting."
}