{
 "ocl_version": "0.1.0",
 "name": "Sewer's Farm Road",
 "slug": "sewer-s-farm-road",
 "confidence": "B",
 "reported_claims": [],
 "ladder": [
  {
   "window_m": 2.0,
   "max_gradient_pct": 33.87336833823866,
   "diagnostic": true,
   "flags": [],
   "start_distance_m": 300.0,
   "end_distance_m": 302.0,
   "start_elevation_m": 208.0495305254839,
   "end_elevation_m": 208.72699789224868,
   "min_gradient_pct": -2.09970665999748
  },
  {
   "window_m": 3.0,
   "max_gradient_pct": 32.23349190278005,
   "diagnostic": true,
   "flags": [],
   "start_distance_m": 300.0,
   "end_distance_m": 303.0,
   "start_elevation_m": 208.0495305254839,
   "end_elevation_m": 209.0165352825673,
   "min_gradient_pct": -1.239729119945802
  },
  {
   "window_m": 5.0,
   "max_gradient_pct": 31.6550227594945,
   "diagnostic": false,
   "flags": [
    "canopy_or_structure"
   ],
   "start_distance_m": 300.0,
   "end_distance_m": 305.0,
   "start_elevation_m": 208.0495305254839,
   "end_elevation_m": 209.63228166345863,
   "min_gradient_pct": 0.15507702215359132
  },
  {
   "window_m": 10.0,
   "max_gradient_pct": 30.755005678086604,
   "diagnostic": false,
   "flags": [
    "canopy_or_structure"
   ],
   "start_distance_m": 295.0,
   "end_distance_m": 305.0,
   "start_elevation_m": 206.55678109564997,
   "end_elevation_m": 209.63228166345863,
   "min_gradient_pct": 1.2016226717210543
  },
  {
   "window_m": 20.0,
   "max_gradient_pct": 29.089675720480273,
   "diagnostic": false,
   "flags": [
    "canopy_or_structure"
   ],
   "start_distance_m": 292.0,
   "end_distance_m": 312.0,
   "start_elevation_m": 205.8149004440403,
   "end_elevation_m": 211.63283558813634,
   "min_gradient_pct": 1.4850516293093108
  },
  {
   "window_m": 25.0,
   "max_gradient_pct": 27.456979326802752,
   "diagnostic": false,
   "flags": [
    "canopy_or_structure"
   ],
   "start_distance_m": 287.0,
   "end_distance_m": 312.0,
   "start_elevation_m": 204.76859075643566,
   "end_elevation_m": 211.63283558813634,
   "min_gradient_pct": 1.598097837646037
  },
  {
   "window_m": 50.0,
   "max_gradient_pct": 20.930330770297534,
   "diagnostic": false,
   "flags": [
    "canopy_or_structure"
   ],
   "start_distance_m": 273.0,
   "end_distance_m": 323.0,
   "start_elevation_m": 202.68339808046832,
   "end_elevation_m": 213.1485634656171,
   "min_gradient_pct": 2.0768200518377284
  },
  {
   "window_m": 100.0,
   "max_gradient_pct": 15.996940376342366,
   "diagnostic": false,
   "flags": [
    "canopy_or_structure"
   ],
   "start_distance_m": 214.0,
   "end_distance_m": 314.0,
   "start_elevation_m": 195.96760809862286,
   "end_elevation_m": 211.96454847496523,
   "min_gradient_pct": 3.8059935520174406
  }
 ],
 "shape": {
  "ascent_concentration": 0.412,
  "concentration_window_frac": 0.25,
  "longest_pitch_10pct_m": 62.0,
  "shape_class": "sustained"
 },
 "length_m": 323.3844670431945,
 "start_elevation_m": 180.1446823485715,
 "end_elevation_m": 213.17397098503318,
 "endpoint_gain_m": 33.02928863646167,
 "overall_gradient_pct": 10.21362866882841,
 "accumulated_ascent_m": 33.080233351704436,
 "window_maxima": {
  "max_5m": {
   "gradient_pct": 31.6550227594945,
   "start_distance_m": 300.0,
   "end_distance_m": 305.0,
   "midpoint_distance_m": 302.5,
   "start_elevation_m": 208.0495305254839,
   "end_elevation_m": 209.63228166345863,
   "start_xy": [
    512874.02802626864,
    144658.15668511446
   ],
   "end_xy": [
    512878.38060724374,
    144655.6959876277
   ]
  },
  "max_10m": {
   "gradient_pct": 30.755005678086604,
   "start_distance_m": 295.0,
   "end_distance_m": 305.0,
   "midpoint_distance_m": 300.0,
   "start_elevation_m": 206.55678109564997,
   "end_elevation_m": 209.63228166345863,
   "start_xy": [
    512869.6750885704,
    144660.61675249526
   ],
   "end_xy": [
    512878.38060724374,
    144655.6959876277
   ]
  },
  "max_20m": {
   "gradient_pct": 29.089675720480273,
   "start_distance_m": 292.0,
   "end_distance_m": 312.0,
   "midpoint_distance_m": 302.0,
   "start_elevation_m": 205.8149004440403,
   "end_elevation_m": 211.63283558813634,
   "start_xy": [
    512867.06347745407,
    144662.09306102595
   ],
   "end_xy": [
    512884.47407800454,
    144652.25075846358
   ]
  },
  "max_25m": {
   "gradient_pct": 27.456979326802752,
   "start_distance_m": 287.0,
   "end_distance_m": 312.0,
   "midpoint_distance_m": 299.5,
   "start_elevation_m": 204.76859075643566,
   "end_elevation_m": 211.63283558813634,
   "start_xy": [
    512862.7109245866,
    144664.5538081648
   ],
   "end_xy": [
    512884.47407800454,
    144652.25075846358
   ]
  },
  "max_50m": {
   "gradient_pct": 20.930330770297534,
   "start_distance_m": 273.0,
   "end_distance_m": 323.0,
   "midpoint_distance_m": 298.0,
   "start_elevation_m": 202.68339808046832,
   "end_elevation_m": 213.1485634656171,
   "start_xy": [
    512850.5231170871,
    144671.44273638708
   ],
   "end_xy": [
    512894.05009062146,
    144646.83781370576
   ]
  },
  "max_100m": {
   "gradient_pct": 15.996940376342366,
   "start_distance_m": 214.0,
   "end_distance_m": 314.0,
   "midpoint_distance_m": 264.0,
   "start_elevation_m": 195.96760809862286,
   "end_elevation_m": 211.96454847496523,
   "start_xy": [
    512808.3091477334,
    144712.43224942987
   ],
   "end_xy": [
    512886.21522227523,
    144651.26667696968
   ]
  }
 },
 "window_minima": {
  "min_5m": {
   "gradient_pct": 0.15507702215359132,
   "start_distance_m": 19.0,
   "end_distance_m": 24.0,
   "midpoint_distance_m": 21.5,
   "start_elevation_m": 180.5030664020057,
   "end_elevation_m": 180.51082025311337,
   "start_xy": [
    512687.0109992778,
    144849.09500817402
   ],
   "end_xy": [
    512687.44798765756,
    144844.11414129936
   ]
  },
  "min_10m": {
   "gradient_pct": 1.2016226717210543,
   "start_distance_m": 21.0,
   "end_distance_m": 31.0,
   "midpoint_distance_m": 26.0,
   "start_elevation_m": 180.54801212671174,
   "end_elevation_m": 180.66817439388385,
   "start_xy": [
    512687.18602775916,
    144847.102681886
   ],
   "end_xy": [
    512688.06198930705,
    144837.1411224156
   ]
  },
  "min_20m": {
   "gradient_pct": 1.4850516293093108,
   "start_distance_m": 4.0,
   "end_distance_m": 24.0,
   "midpoint_distance_m": 14.0,
   "start_elevation_m": 180.2138099272515,
   "end_elevation_m": 180.51082025311337,
   "start_xy": [
    512685.69697034307,
    144864.03733986153
   ],
   "end_xy": [
    512687.44798765756,
    144844.11414129936
   ]
  },
  "min_25m": {
   "gradient_pct": 1.598097837646037,
   "start_distance_m": 0.0,
   "end_distance_m": 25.0,
   "midpoint_distance_m": 12.5,
   "start_elevation_m": 180.1446823485715,
   "end_elevation_m": 180.54420680798302,
   "start_xy": [
    512685.347,
    144868.022
   ],
   "end_xy": [
    512687.53599807876,
    144843.11802174547
   ]
  },
  "min_50m": {
   "gradient_pct": 2.0768200518377284,
   "start_distance_m": 0.0,
   "end_distance_m": 50.0,
   "midpoint_distance_m": 25.0,
   "start_elevation_m": 180.1446823485715,
   "end_elevation_m": 181.18309237449037,
   "start_xy": [
    512685.347,
    144868.022
   ],
   "end_xy": [
    512689.7289653985,
    144818.2143920194
   ]
  },
  "min_100m": {
   "gradient_pct": 3.8059935520174406,
   "start_distance_m": 0.0,
   "end_distance_m": 100.0,
   "midpoint_distance_m": 50.0,
   "start_elevation_m": 180.1446823485715,
   "end_elevation_m": 183.95067590058895,
   "start_xy": [
    512685.347,
    144868.022
   ],
   "end_xy": [
    512720.93628005177,
    144783.15247974443
   ]
  }
 },
 "diagnostic_window_maxima": {
  "max_2m": {
   "gradient_pct": 33.87336833823866,
   "start_distance_m": 300.0,
   "end_distance_m": 302.0,
   "midpoint_distance_m": 301.0,
   "start_elevation_m": 208.0495305254839,
   "end_elevation_m": 208.72699789224868,
   "start_xy": [
    512874.02802626864,
    144658.15668511446
   ],
   "end_xy": [
    512875.7687697931,
    144657.17189570318
   ]
  },
  "max_3m": {
   "gradient_pct": 32.23349190278005,
   "start_distance_m": 300.0,
   "end_distance_m": 303.0,
   "midpoint_distance_m": 301.5,
   "start_elevation_m": 208.0495305254839,
   "end_elevation_m": 209.0165352825673,
   "start_xy": [
    512874.02802626864,
    144658.15668511446
   ],
   "end_xy": [
    512876.6392367201,
    144656.67966881022
   ]
  }
 },
 "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": {
  "overhead_obstruction": {
   "obstruction_threshold_m": 2.0,
   "obstructed_fraction": 0.111,
   "obstruction_max_height_m": 25.3,
   "flagged_windows_m": [
    5,
    10,
    20,
    25,
    50,
    100
   ]
  },
  "review": [],
  "extent": [
   "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/bulk_dtm_1m/TQ1040.tif"
  ],
  "calculated_at": "2026-08-19T18:46:38+00:00",
  "road_source": "OpenStreetMap (local PBF extract)",
  "road_attribution": "\u00a9 OpenStreetMap contributors, ODbL",
  "osm_pbf_path": "data/cache/pbf/england-2026-08-12.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": [
   "TQ1040.tif"
  ],
  "climb_origin": "discovered",
  "notes": "Coarse pass: max 10.1% over 200 m (Terrain 50), gain 20.1 m over 189 m way. EXTENDED by graph walk: +3 segment(s) at base, +0 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): qualified-steep."
 },
 "area": {
  "place": "Abinger Bottom",
  "county": "Surrey"
 }
}