{
 "ocl_version": "0.1.0",
 "name": "Little Quantock Lane",
 "slug": "little-quantock-lane",
 "confidence": "B",
 "reported_claims": [],
 "ladder": [
  {
   "window_m": 2.0,
   "max_gradient_pct": 53.32358696973216,
   "diagnostic": true,
   "flags": [
    "canopy_or_structure"
   ],
   "start_distance_m": 589.0,
   "end_distance_m": 591.0,
   "start_elevation_m": 181.4403552869771,
   "end_elevation_m": 182.50682702637175,
   "min_gradient_pct": -25.018571872648465
  },
  {
   "window_m": 3.0,
   "max_gradient_pct": 41.500769759863,
   "diagnostic": true,
   "flags": [
    "canopy_or_structure"
   ],
   "start_distance_m": 589.0,
   "end_distance_m": 592.0,
   "start_elevation_m": 181.4403552869771,
   "end_elevation_m": 182.685378379773,
   "min_gradient_pct": -24.057982240462177
  },
  {
   "window_m": 5.0,
   "max_gradient_pct": 26.473005471358988,
   "diagnostic": false,
   "flags": [
    "canopy_or_structure"
   ],
   "start_distance_m": 589.0,
   "end_distance_m": 594.0,
   "start_elevation_m": 181.4403552869771,
   "end_elevation_m": 182.76400556054506,
   "min_gradient_pct": -20.308702033182158
  },
  {
   "window_m": 10.0,
   "max_gradient_pct": 21.494488886289105,
   "diagnostic": false,
   "flags": [],
   "start_distance_m": 728.0,
   "end_distance_m": 738.0,
   "start_elevation_m": 193.72603642417852,
   "end_elevation_m": 195.87548531280743,
   "min_gradient_pct": -18.366448187869935
  },
  {
   "window_m": 20.0,
   "max_gradient_pct": 20.593606324127904,
   "diagnostic": false,
   "flags": [],
   "start_distance_m": 718.0,
   "end_distance_m": 738.0,
   "start_elevation_m": 191.75676404798185,
   "end_elevation_m": 195.87548531280743,
   "min_gradient_pct": -12.939621426946672
  },
  {
   "window_m": 25.0,
   "max_gradient_pct": 20.451314683223018,
   "diagnostic": false,
   "flags": [],
   "start_distance_m": 712.0,
   "end_distance_m": 737.0,
   "start_elevation_m": 190.5397110445575,
   "end_elevation_m": 195.65253971536325,
   "min_gradient_pct": -11.786087934790203
  },
  {
   "window_m": 50.0,
   "max_gradient_pct": 17.112097158031077,
   "diagnostic": false,
   "flags": [],
   "start_distance_m": 712.0,
   "end_distance_m": 762.0,
   "start_elevation_m": 190.5397110445575,
   "end_elevation_m": 199.09575962357303,
   "min_gradient_pct": -7.713245991416954
  },
  {
   "window_m": 100.0,
   "max_gradient_pct": 12.375546308087477,
   "diagnostic": false,
   "flags": [],
   "start_distance_m": 667.0,
   "end_distance_m": 767.0,
   "start_elevation_m": 186.98914958282413,
   "end_elevation_m": 199.3646958909116,
   "min_gradient_pct": -5.198029678522062
  }
 ],
 "shape": {
  "ascent_concentration": 0.448,
  "concentration_window_frac": 0.25,
  "longest_pitch_10pct_m": 69.0,
  "shape_class": "sustained"
 },
 "length_m": 1405.00000000001,
 "start_elevation_m": 166.1662874848634,
 "end_elevation_m": 221.75706342450795,
 "endpoint_gain_m": 55.590775939644544,
 "overall_gradient_pct": 3.956638856914174,
 "accumulated_ascent_m": 75.14745493426639,
 "window_maxima": {
  "max_5m": {
   "gradient_pct": 26.473005471358988,
   "start_distance_m": 589.0,
   "end_distance_m": 594.0,
   "midpoint_distance_m": 591.5,
   "start_elevation_m": 181.4403552869771,
   "end_elevation_m": 182.76400556054506,
   "start_xy": [
    315571.45536979905,
    135524.49151597972
   ],
   "end_xy": [
    315571.0474064067,
    135529.47484413284
   ]
  },
  "max_10m": {
   "gradient_pct": 21.494488886289105,
   "start_distance_m": 728.0,
   "end_distance_m": 738.0,
   "midpoint_distance_m": 733.0,
   "start_elevation_m": 193.72603642417852,
   "end_elevation_m": 195.87548531280743,
   "start_xy": [
    315481.62196139124,
    135596.05302891703
   ],
   "end_xy": [
    315475.38930836157,
    135603.85119517322
   ]
  },
  "max_20m": {
   "gradient_pct": 20.593606324127904,
   "start_distance_m": 718.0,
   "end_distance_m": 738.0,
   "midpoint_distance_m": 728.0,
   "start_elevation_m": 191.75676404798185,
   "end_elevation_m": 195.87548531280743,
   "start_xy": [
    315489.43843307707,
    135589.95313786482
   ],
   "end_xy": [
    315475.38930836157,
    135603.85119517322
   ]
  },
  "max_25m": {
   "gradient_pct": 20.451314683223018,
   "start_distance_m": 712.0,
   "end_distance_m": 737.0,
   "midpoint_distance_m": 724.5,
   "start_elevation_m": 190.5397110445575,
   "end_elevation_m": 195.65253971536325,
   "start_xy": [
    315494.6014394889,
    135586.8964486752
   ],
   "end_xy": [
    315475.97917889134,
    135603.04369738264
   ]
  },
  "max_50m": {
   "gradient_pct": 17.112097158031077,
   "start_distance_m": 712.0,
   "end_distance_m": 762.0,
   "midpoint_distance_m": 737.0,
   "start_elevation_m": 190.5397110445575,
   "end_elevation_m": 199.09575962357303,
   "start_xy": [
    315494.6014394889,
    135586.8964486752
   ],
   "end_xy": [
    315462.93153602007,
    135624.33987272994
   ]
  },
  "max_100m": {
   "gradient_pct": 12.375546308087477,
   "start_distance_m": 667.0,
   "end_distance_m": 767.0,
   "midpoint_distance_m": 717.0,
   "start_elevation_m": 186.98914958282413,
   "end_elevation_m": 199.3646958909116,
   "start_xy": [
    315536.4679807164,
    135573.00251965536
   ],
   "end_xy": [
    315460.5317802934,
    135628.72634843923
   ]
  }
 },
 "window_minima": {
  "min_5m": {
   "gradient_pct": -20.308702033182158,
   "start_distance_m": 386.0,
   "end_distance_m": 391.0,
   "midpoint_distance_m": 388.5,
   "start_elevation_m": 180.89342397596232,
   "end_elevation_m": 179.8779888743032,
   "start_xy": [
    315419.82184177643,
    135404.11359435748
   ],
   "end_xy": [
    315423.4015923813,
    135407.60435123206
   ]
  },
  "min_10m": {
   "gradient_pct": -18.366448187869935,
   "start_distance_m": 381.0,
   "end_distance_m": 391.0,
   "midpoint_distance_m": 386.0,
   "start_elevation_m": 181.7146336930902,
   "end_elevation_m": 179.8779888743032,
   "start_xy": [
    315416.2415911501,
    135400.62335003182
   ],
   "end_xy": [
    315423.4015923813,
    135407.60435123206
   ]
  },
  "min_20m": {
   "gradient_pct": -12.939621426946672,
   "start_distance_m": 374.0,
   "end_distance_m": 394.0,
   "midpoint_distance_m": 384.0,
   "start_elevation_m": 182.25456232300218,
   "end_elevation_m": 179.66663803761284,
   "start_xy": [
    315411.2297402947,
    135395.73649542697
   ],
   "end_xy": [
    315425.5497427571,
    135409.69849782748
   ]
  },
  "min_25m": {
   "gradient_pct": -11.786087934790203,
   "start_distance_m": 374.0,
   "end_distance_m": 399.0,
   "midpoint_distance_m": 386.5,
   "start_elevation_m": 182.25456232300218,
   "end_elevation_m": 179.30804033930463,
   "start_xy": [
    315411.2297402947,
    135395.73649542697
   ],
   "end_xy": [
    315429.129493362,
    135413.18925470204
   ]
  },
  "min_50m": {
   "gradient_pct": -7.713245991416954,
   "start_distance_m": 357.0,
   "end_distance_m": 407.0,
   "midpoint_distance_m": 382.0,
   "start_elevation_m": 182.79657607777182,
   "end_elevation_m": 178.93995308206334,
   "start_xy": [
    315399.0578882081,
    135383.86863962185
   ],
   "end_xy": [
    315434.90369055845,
    135418.7233135779
   ]
  },
  "min_100m": {
   "gradient_pct": -5.198029678522062,
   "start_distance_m": 1026.0,
   "end_distance_m": 1126.0,
   "midpoint_distance_m": 1076.0,
   "start_elevation_m": 211.56699776207242,
   "end_elevation_m": 206.36896808355036,
   "start_xy": [
    315347.96183820674,
    135839.24049452314
   ],
   "end_xy": [
    315268.3746614675,
    135899.21558833998
   ]
  }
 },
 "diagnostic_window_maxima": {
  "max_2m": {
   "gradient_pct": 53.32358696973216,
   "start_distance_m": 589.0,
   "end_distance_m": 591.0,
   "midpoint_distance_m": 590.0,
   "start_elevation_m": 181.4403552869771,
   "end_elevation_m": 182.50682702637175,
   "start_xy": [
    315571.45536979905,
    135524.49151597972
   ],
   "end_xy": [
    315571.29240466777,
    135526.48486525504
   ]
  },
  "max_3m": {
   "gradient_pct": 41.500769759863,
   "start_distance_m": 589.0,
   "end_distance_m": 592.0,
   "midpoint_distance_m": 590.5,
   "start_elevation_m": 181.4403552869771,
   "end_elevation_m": 182.685378379773,
   "start_xy": [
    315571.45536979905,
    135524.49151597972
   ],
   "end_xy": [
    315571.2103715363,
    135527.48149485735
   ]
  }
 },
 "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": 0.043,
   "obstruction_max_height_m": 10.82,
   "flagged_windows_m": [
    2,
    3,
    5
   ]
  },
  "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/ST1035.tif",
   "data/cache/england/bulk_dtm_1m/ST1535.tif"
  ],
  "calculated_at": "2026-08-19T18:39:40+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": [
   "ST1035.tif",
   "ST1535.tif"
  ],
  "route_summit_trim_m": 523.9,
  "route_summit_trim_loss_m": 8.0,
  "climb_origin": "discovered",
  "notes": "Coarse pass: max 9.6% over 200 m (Terrain 50), gain 28.0 m over 1293 m way. EXTENDED by graph walk: +2 segment(s) at base, +0 at top (stop: base=no_descending_continuation, top=no_ascending_continuation; min_avg=2.0%). Review before adopting. DEDUPE: absorbed 1 overlapping proposal(s): cockercombe-road ADOPTED (England launch slice 2026-08-16): clean-steep."
 },
 "area": {
  "place": "Triscombe",
  "county": "Somerset"
 }
}