{
 "ocl_version": "0.1.0",
 "name": "Belmont Road",
 "slug": "belmont-road",
 "confidence": "B",
 "reported_claims": [],
 "ladder": [
  {
   "window_m": 2.0,
   "max_gradient_pct": 46.76080780216694,
   "diagnostic": true,
   "flags": [
    "structure_excluded",
    "canopy_or_structure"
   ],
   "start_distance_m": 1947.0,
   "end_distance_m": 1949.0,
   "start_elevation_m": 196.74412299935477,
   "end_elevation_m": 197.6793391553981,
   "min_gradient_pct": -49.328855748730405,
   "suppressed_max_gradient_pct": 70.50115558475483,
   "suppressed_location_m": [
    435.0,
    437.0
   ]
  },
  {
   "window_m": 3.0,
   "max_gradient_pct": 35.778859045914636,
   "diagnostic": true,
   "flags": [
    "structure_excluded",
    "canopy_or_structure"
   ],
   "start_distance_m": 1947.0,
   "end_distance_m": 1950.0,
   "start_elevation_m": 196.74412299935477,
   "end_elevation_m": 197.8174887707322,
   "min_gradient_pct": -42.55962525472322,
   "suppressed_max_gradient_pct": 62.443181113746014,
   "suppressed_location_m": [
    435.0,
    438.0
   ]
  },
  {
   "window_m": 5.0,
   "max_gradient_pct": 30.958599365133068,
   "diagnostic": false,
   "flags": [
    "structure_excluded",
    "placement_excluded"
   ],
   "start_distance_m": 2104.0,
   "end_distance_m": 2109.0,
   "start_elevation_m": 218.9755905021086,
   "end_elevation_m": 220.52352047036524,
   "min_gradient_pct": -30.422828252798695,
   "suppressed_max_gradient_pct": 51.01557483110355,
   "suppressed_location_m": [
    435.0,
    440.0
   ]
  },
  {
   "window_m": 10.0,
   "max_gradient_pct": 29.893093629063685,
   "diagnostic": false,
   "flags": [
    "structure_excluded"
   ],
   "start_distance_m": 2098.0,
   "end_distance_m": 2108.0,
   "start_elevation_m": 217.26888498125672,
   "end_elevation_m": 220.2581943441631,
   "min_gradient_pct": -19.50117234163173,
   "suppressed_max_gradient_pct": 34.952767754681986,
   "suppressed_location_m": [
    432.0,
    442.0
   ]
  },
  {
   "window_m": 20.0,
   "max_gradient_pct": 26.107743184017238,
   "diagnostic": false,
   "flags": [],
   "start_distance_m": 2097.0,
   "end_distance_m": 2117.0,
   "start_elevation_m": 216.9993425378433,
   "end_elevation_m": 222.22089117464674,
   "min_gradient_pct": -15.637168536899395
  },
  {
   "window_m": 25.0,
   "max_gradient_pct": 24.517027394902357,
   "diagnostic": false,
   "flags": [],
   "start_distance_m": 2096.0,
   "end_distance_m": 2121.0,
   "start_elevation_m": 216.7964855087872,
   "end_elevation_m": 222.9257423575128,
   "min_gradient_pct": -15.12347811946438
  },
  {
   "window_m": 50.0,
   "max_gradient_pct": 18.019160627722215,
   "diagnostic": false,
   "flags": [],
   "start_distance_m": 2071.0,
   "end_distance_m": 2121.0,
   "start_elevation_m": 213.9161620436517,
   "end_elevation_m": 222.9257423575128,
   "min_gradient_pct": -13.273155667646165
  },
  {
   "window_m": 100.0,
   "max_gradient_pct": 15.879931089381076,
   "diagnostic": false,
   "flags": [
    "canopy_or_structure"
   ],
   "start_distance_m": 2021.0,
   "end_distance_m": 2121.0,
   "start_elevation_m": 207.04581126813173,
   "end_elevation_m": 222.9257423575128,
   "min_gradient_pct": -9.756536803710418
  }
 ],
 "shape": {
  "ascent_concentration": 0.405,
  "concentration_window_frac": 0.25,
  "longest_pitch_10pct_m": 63.0,
  "shape_class": "sustained"
 },
 "length_m": 2133.9999999999836,
 "start_elevation_m": 157.11248771667482,
 "end_elevation_m": 223.0279453822841,
 "endpoint_gain_m": 65.91545766560927,
 "overall_gradient_pct": 3.088821821256315,
 "accumulated_ascent_m": 116.89811134387907,
 "window_maxima": {
  "max_5m": {
   "gradient_pct": 30.958599365133068,
   "start_distance_m": 2104.0,
   "end_distance_m": 2109.0,
   "midpoint_distance_m": 2106.5,
   "start_elevation_m": 218.9755905021086,
   "end_elevation_m": 220.52352047036524,
   "start_xy": [
    400714.6086163904,
    349714.33298693964
   ],
   "end_xy": [
    400718.6899926862,
    349711.4446718473
   ]
  },
  "max_10m": {
   "gradient_pct": 29.893093629063685,
   "start_distance_m": 2098.0,
   "end_distance_m": 2108.0,
   "midpoint_distance_m": 2103.0,
   "start_elevation_m": 217.26888498125672,
   "end_elevation_m": 220.2581943441631,
   "start_xy": [
    400709.71164124506,
    349717.7999207847
   ],
   "end_xy": [
    400717.87396820507,
    349712.0226891881
   ]
  },
  "max_20m": {
   "gradient_pct": 26.107743184017238,
   "start_distance_m": 2097.0,
   "end_distance_m": 2117.0,
   "midpoint_distance_m": 2107.0,
   "start_elevation_m": 216.9993425378433,
   "end_elevation_m": 222.22089117464674,
   "start_xy": [
    400708.8948510415,
    349718.37685550685
   ],
   "end_xy": [
    400725.2197988949,
    349706.82280911616
   ]
  },
  "max_25m": {
   "gradient_pct": 24.517027394902357,
   "start_distance_m": 2096.0,
   "end_distance_m": 2121.0,
   "midpoint_distance_m": 2108.5,
   "start_elevation_m": 216.7964855087872,
   "end_elevation_m": 222.9257423575128,
   "start_xy": [
    400708.07878729526,
    349718.9548173325
   ],
   "end_xy": [
    400728.4847247559,
    349704.5119103135
   ]
  },
  "max_50m": {
   "gradient_pct": 18.019160627722215,
   "start_distance_m": 2071.0,
   "end_distance_m": 2121.0,
   "midpoint_distance_m": 2096.0,
   "start_elevation_m": 213.9161620436517,
   "end_elevation_m": 222.9257423575128,
   "start_xy": [
    400703.22119366756,
    349742.42548735894
   ],
   "end_xy": [
    400728.4847247559,
    349704.5119103135
   ]
  },
  "max_100m": {
   "gradient_pct": 15.879931089381076,
   "start_distance_m": 2021.0,
   "end_distance_m": 2121.0,
   "midpoint_distance_m": 2071.0,
   "start_elevation_m": 207.04581126813173,
   "end_elevation_m": 222.9257423575128,
   "start_xy": [
    400686.5690252268,
    349764.9716345595
   ],
   "end_xy": [
    400728.4847247559,
    349704.5119103135
   ]
  }
 },
 "window_minima": {
  "min_5m": {
   "gradient_pct": -30.422828252798695,
   "start_distance_m": 1616.0,
   "end_distance_m": 1621.0,
   "midpoint_distance_m": 1618.5,
   "start_elevation_m": 189.7612797954686,
   "end_elevation_m": 188.24013838282866,
   "start_xy": [
    400455.8587768875,
    350029.447494884
   ],
   "end_xy": [
    400455.6982071611,
    350024.4503012544
   ]
  },
  "min_10m": {
   "gradient_pct": -19.50117234163173,
   "start_distance_m": 1392.0,
   "end_distance_m": 1402.0,
   "midpoint_distance_m": 1397.0,
   "start_elevation_m": 194.5011730723538,
   "end_elevation_m": 192.55105583819062,
   "start_xy": [
    400429.0089342136,
    350238.6178242712
   ],
   "end_xy": [
    400434.38334895036,
    350230.1848153349
   ]
  },
  "min_20m": {
   "gradient_pct": -15.637168536899395,
   "start_distance_m": 1382.0,
   "end_distance_m": 1402.0,
   "midpoint_distance_m": 1392.0,
   "start_elevation_m": 195.6784895455705,
   "end_elevation_m": 192.55105583819062,
   "start_xy": [
    400423.6343896224,
    350247.0507514866
   ],
   "end_xy": [
    400434.38334895036,
    350230.1848153349
   ]
  },
  "min_25m": {
   "gradient_pct": -15.12347811946438,
   "start_distance_m": 1377.0,
   "end_distance_m": 1402.0,
   "midpoint_distance_m": 1389.5,
   "start_elevation_m": 196.33192536805672,
   "end_elevation_m": 192.55105583819062,
   "start_xy": [
    400420.79014209885,
    350251.1616560919
   ],
   "end_xy": [
    400434.38334895036,
    350230.1848153349
   ]
  },
  "min_50m": {
   "gradient_pct": -13.273155667646165,
   "start_distance_m": 1352.0,
   "end_distance_m": 1402.0,
   "midpoint_distance_m": 1377.0,
   "start_elevation_m": 199.1876336720137,
   "end_elevation_m": 192.55105583819062,
   "start_xy": [
    400406.28169413836,
    350271.5210465024
   ],
   "end_xy": [
    400434.38334895036,
    350230.1848153349
   ]
  },
  "min_100m": {
   "gradient_pct": -9.756536803710418,
   "start_distance_m": 1302.0,
   "end_distance_m": 1402.0,
   "midpoint_distance_m": 1352.0,
   "start_elevation_m": 202.30759264190104,
   "end_elevation_m": 192.55105583819062,
   "start_xy": [
    400378.0385493483,
    350312.7688196997
   ],
   "end_xy": [
    400434.38334895036,
    350230.1848153349
   ]
  }
 },
 "diagnostic_window_maxima": {
  "max_2m": {
   "gradient_pct": 46.76080780216694,
   "start_distance_m": 1947.0,
   "end_distance_m": 1949.0,
   "midpoint_distance_m": 1948.0,
   "start_elevation_m": 196.74412299935477,
   "end_elevation_m": 197.6793391553981,
   "start_xy": [
    400625.2873170386,
    349776.6820585168
   ],
   "end_xy": [
    400626.6144920522,
    349775.18586136284
   ]
  },
  "max_3m": {
   "gradient_pct": 35.778859045914636,
   "start_distance_m": 1947.0,
   "end_distance_m": 1950.0,
   "midpoint_distance_m": 1948.5,
   "start_elevation_m": 196.74412299935477,
   "end_elevation_m": 197.8174887707322,
   "start_xy": [
    400625.2873170386,
    349776.6820585168
   ],
   "end_xy": [
    400627.27760942944,
    349774.4373462101
   ]
  }
 },
 "diagnostic_note": "Windows <=3 m are at raster-noise scale (1-sigma raster noise alone is roughly +/-7 pp at 2 m and +/-5 pp at 3 m on a 1 m DTM). Diagnostic use only: never a headline or ranking value.",
 "quality_summary": {
  "structure_suppression": {
   "masked_fraction": 0.006,
   "windows_resited": [
    2.0,
    3.0,
    5.0,
    10.0
   ],
   "windows_unresolved": []
  },
  "placement_suppression": {
   "masked_fraction": 0.037,
   "windows_resited": [
    5.0
   ],
   "windows_unresolved": []
  },
  "overhead_obstruction": {
   "obstruction_threshold_m": 2.0,
   "obstructed_fraction": 0.167,
   "obstruction_max_height_m": 19.95,
   "flagged_windows_m": [
    2,
    3,
    100
   ]
  },
  "excluded_ranges_m": [
   [
    182.0,
    187.0
   ],
   [
    350.0,
    380.0
   ],
   [
    420.0,
    460.0
   ]
  ],
  "review": [],
  "extent": [
   "may_start_earlier",
   "may_continue_beyond_end"
  ]
 },
 "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/dtm_1m/E398000_N348000_2000m.tif",
   "data/cache/england/dtm_1m/E400000_N348000_2000m.tif",
   "data/cache/england/dtm_1m/E398000_N350000_2000m.tif",
   "data/cache/england/dtm_1m/E400000_N350000_2000m.tif"
  ],
  "calculated_at": "2026-09-15T02:48:53+00:00",
  "road_source": "OpenStreetMap (local PBF extract)",
  "road_attribution": "\u00a9 OpenStreetMap contributors, ODbL",
  "osm_pbf_path": "data/cache/pbf/england-2026-08-27.osm.pbf",
  "osm_snapshot": "2026-08-26T20:22:15Z",
  "run_id": "retro-260914",
  "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": [
   "E398000_N348000_2000m.tif",
   "E400000_N348000_2000m.tif",
   "E398000_N350000_2000m.tif",
   "E400000_N350000_2000m.tif"
  ],
  "route_cut_m": 2134.0,
  "climb_origin": "discovered",
  "structure_own_ways": "none \u2014 the route carried no way list; own decks unmasked",
  "license": "ODbL-1.0",
  "license_url": "https://howsteep.org/licensing"
 },
 "area": {
  "place": "Basford Green",
  "county": "Staffordshire"
 }
}