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Bolenowe Road

353.4 m · net rise 23.4 m · total ascent 33.2 m · overall 6.6% · evidence quality U (needs confirmation) · Bolenowe · Cornwall ·

Shape: stepped — 45% of the climbing sits in a quarter of the distance; longest continuous stretch at 10%+ is 55 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.

Gradient ladder what do windows mean?

WindowMaximumLocated at
2 m (diagnostic)≈37%290–292 munder overhead cover terrain reads 88.1% at 139–141 m across a structure — excluded
3 m (diagnostic)≈31%127–130 munder overhead cover terrain reads 80.9% at 138–141 m across a structure — excluded
5 m≈26%55–60 munder overhead cover terrain reads 68.4% at 138–143 m across a structure — excluded
10 m≈17%51–61 munder overhead cover terrain reads 37.1% at 137–147 m across a structure — excluded
20 m≈13.5%100–120 munder overhead cover terrain reads 21.4% at 72–92 m across a structure — excluded
25 m≈10.4%271–296 munder overhead cover terrain reads 20.0% at 72–97 m across a structure — excluded
50 m≈7.6%15–65 munder overhead cover terrain reads 15.6% at 69–119 m across a structure — excluded
100 m≈4.6%192–292 munder overhead cover terrain reads 12.3% at 45–145 m across a structure — excluded

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

No aerial layer here: Britain has no open or government source of aerial photography at road scale — the pan-government APGB imagery is licensed to the public sector only, unlike the LiDAR this survey is measured from. Street View, where it exists, is the visual check.

This climb's data: OCL JSON — the full gradient ladder, quality flags and provenance in the OpenClimb Ladder format.

Access: Listed 2026-09-11 (texture re-measure): with the step masked the steepest 25 m reads 10.4 %, below the ranking door — kept as a listed page.

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 ·

Route colour = gradient over a 25 m window: <10% 10–20% 20–25% ≥25%

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

Bolenowe Road LiDAR hillshade map with contours

Profile

The map, profile and gradient chart share one position — move your pointer over them and the marker follows. Colors are the gradient bands; the shaded span is the steepest 25 m. Any 25 m figure is good to about a point either way (why).

Bolenowe Road elevation profile
Bolenowe Road rolling gradient profile
 

Measurement card

ElevationEnvironment Agency — EA LIDAR Composite DTM 1m (2022)
Resolution / CRS1.0 m grid, EPSG:27700; sampled every 1.0 m, bilinear interpolation
TilesSW6535.tif
Road centrelineOpenStreetMap (local PBF extract)
Quality statusevidence quality U; review flags: short window divergence
AnalysisOCL 0.1.0, analysis 0.1.0, run texture-uk-england-260911, calculated 2026-09-11

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/SW6535.tif"
  ],
  "calculated_at": "2026-09-11T23:25:04+00:00",
  "road_source": "OpenStreetMap (local PBF extract)",
  "road_attribution": "\u00a9 OpenStreetMap contributors, ODbL",
  "osm_pbf_path": "output/texture-uk-england/batch-england-rchunk00.pbf",
  "osm_snapshot": "",
  "run_id": "texture-uk-england-260911",
  "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": [
    "SW6535.tif"
  ],
  "climb_origin": "discovered",
  "license": "ODbL-1.0",
  "license_url": "https://howsteep.org/licensing"
}