{
 "ocl_version": "0.1.0",
 "name": "Castle Idris to Pen y Garn",
 "slug": "discovered-lane-52-4285-3-1566",
 "confidence": "B",
 "reported_claims": [],
 "ladder": [
  {
   "window_m": 2.0,
   "max_gradient_pct": 40.570001154753754,
   "diagnostic": true,
   "flags": [
    "structure_excluded"
   ],
   "start_distance_m": 1099.0,
   "end_distance_m": 1101.0,
   "start_elevation_m": 285.85802112661884,
   "end_elevation_m": 286.6694211497139,
   "min_gradient_pct": -20.940999367113022,
   "suppressed_max_gradient_pct": 53.00179204033384,
   "suppressed_location_m": [
    1162.0,
    1164.0
   ]
  },
  {
   "window_m": 3.0,
   "max_gradient_pct": 40.58428528375089,
   "diagnostic": true,
   "flags": [
    "structure_excluded"
   ],
   "start_distance_m": 1099.0,
   "end_distance_m": 1102.0,
   "start_elevation_m": 285.85802112661884,
   "end_elevation_m": 287.07554968513136,
   "min_gradient_pct": -16.292153911016765,
   "suppressed_max_gradient_pct": 48.130996450366105,
   "suppressed_location_m": [
    1162.0,
    1165.0
   ]
  },
  {
   "window_m": 5.0,
   "max_gradient_pct": 39.26012807848224,
   "diagnostic": false,
   "flags": [],
   "start_distance_m": 1098.0,
   "end_distance_m": 1103.0,
   "start_elevation_m": 285.4978517099071,
   "end_elevation_m": 287.4608581138312,
   "min_gradient_pct": -11.39152686361058
  },
  {
   "window_m": 10.0,
   "max_gradient_pct": 31.566992216397125,
   "diagnostic": false,
   "flags": [
    "structure_excluded"
   ],
   "start_distance_m": 1096.0,
   "end_distance_m": 1106.0,
   "start_elevation_m": 285.04954313102184,
   "end_elevation_m": 288.20624235266155,
   "min_gradient_pct": -7.790440173411071,
   "suppressed_max_gradient_pct": 34.5557657999251,
   "suppressed_location_m": [
    1162.0,
    1172.0
   ]
  },
  {
   "window_m": 20.0,
   "max_gradient_pct": 22.249865940985387,
   "diagnostic": false,
   "flags": [
    "structure_excluded"
   ],
   "start_distance_m": 1232.0,
   "end_distance_m": 1252.0,
   "start_elevation_m": 301.57318241501207,
   "end_elevation_m": 306.02315560320915,
   "min_gradient_pct": -4.382170883332037,
   "suppressed_max_gradient_pct": 25.628319913410564,
   "suppressed_location_m": [
    1152.0,
    1172.0
   ]
  },
  {
   "window_m": 25.0,
   "max_gradient_pct": 21.047068452028952,
   "diagnostic": false,
   "flags": [
    "structure_excluded"
   ],
   "start_distance_m": 1319.0,
   "end_distance_m": 1344.0,
   "start_elevation_m": 315.1953194994805,
   "end_elevation_m": 320.4570866124877,
   "min_gradient_pct": -4.029162800045242,
   "suppressed_max_gradient_pct": 23.215396788634735,
   "suppressed_location_m": [
    1147.0,
    1172.0
   ]
  },
  {
   "window_m": 50.0,
   "max_gradient_pct": 20.454882950815204,
   "diagnostic": false,
   "flags": [],
   "start_distance_m": 1297.0,
   "end_distance_m": 1347.0,
   "start_elevation_m": 310.7796133914065,
   "end_elevation_m": 321.0070548668141,
   "min_gradient_pct": -3.122344959439488
  },
  {
   "window_m": 100.0,
   "max_gradient_pct": 17.672339085390547,
   "diagnostic": false,
   "flags": [],
   "start_distance_m": 1282.0,
   "end_distance_m": 1382.0,
   "start_elevation_m": 308.58402706760216,
   "end_elevation_m": 326.2563661529927,
   "min_gradient_pct": -1.6424649693367428
  }
 ],
 "shape": {
  "ascent_concentration": 0.44,
  "concentration_window_frac": 0.25,
  "longest_pitch_10pct_m": 122.0,
  "shape_class": "sustained"
 },
 "length_m": 4438.4821004442965,
 "start_elevation_m": 231.96301286248678,
 "end_elevation_m": 443.1283899143066,
 "endpoint_gain_m": 211.1653770518198,
 "overall_gradient_pct": 4.757603439037908,
 "accumulated_ascent_m": 226.53451191689786,
 "window_maxima": {
  "max_5m": {
   "gradient_pct": 39.26012807848224,
   "start_distance_m": 1098.0,
   "end_distance_m": 1103.0,
   "midpoint_distance_m": 1100.5,
   "start_elevation_m": 285.4978517099071,
   "end_elevation_m": 287.4608581138312,
   "start_xy": [
    321418.60842357104,
    281786.45520202664
   ],
   "end_xy": [
    321413.78660178016,
    281787.77808830916
   ]
  },
  "max_10m": {
   "gradient_pct": 31.566992216397125,
   "start_distance_m": 1096.0,
   "end_distance_m": 1106.0,
   "midpoint_distance_m": 1101.0,
   "start_elevation_m": 285.04954313102184,
   "end_elevation_m": 288.20624235266155,
   "start_xy": [
    321420.56689242675,
    281786.25325416034
   ],
   "end_xy": [
    321410.8933449189,
    281788.5712236478
   ]
  },
  "max_20m": {
   "gradient_pct": 22.249865940985387,
   "start_distance_m": 1232.0,
   "end_distance_m": 1252.0,
   "midpoint_distance_m": 1242.0,
   "start_elevation_m": 301.57318241501207,
   "end_elevation_m": 306.02315560320915,
   "start_xy": [
    321288.9002420062,
    281818.34531380446
   ],
   "end_xy": [
    321270.6272042756,
    281826.47525855876
   ]
  },
  "max_25m": {
   "gradient_pct": 21.047068452028952,
   "start_distance_m": 1319.0,
   "end_distance_m": 1344.0,
   "midpoint_distance_m": 1331.5,
   "start_elevation_m": 315.1953194994805,
   "end_elevation_m": 320.4570866124877,
   "start_xy": [
    321217.0040431583,
    281865.745553963
   ],
   "end_xy": [
    321198.1355262731,
    281882.1461336404
   ]
  },
  "max_50m": {
   "gradient_pct": 20.454882950815204,
   "start_distance_m": 1297.0,
   "end_distance_m": 1347.0,
   "midpoint_distance_m": 1322.0,
   "start_elevation_m": 310.7796133914065,
   "end_elevation_m": 321.0070548668141,
   "start_xy": [
    321233.6088616411,
    281851.31364604435
   ],
   "end_xy": [
    321195.8713331059,
    281884.1142364007
   ]
  },
  "max_100m": {
   "gradient_pct": 17.672339085390547,
   "start_distance_m": 1282.0,
   "end_distance_m": 1382.0,
   "midpoint_distance_m": 1332.0,
   "start_elevation_m": 308.58402706760216,
   "end_elevation_m": 326.2563661529927,
   "start_xy": [
    321244.9301291181,
    281841.47347917577
   ],
   "end_xy": [
    321168.17013322865,
    281905.3038000449
   ]
  }
 },
 "window_minima": {
  "min_5m": {
   "gradient_pct": -11.39152686361058,
   "start_distance_m": 1131.0,
   "end_distance_m": 1136.0,
   "midpoint_distance_m": 1133.5,
   "start_elevation_m": 290.6084192244647,
   "end_elevation_m": 290.03884288128415,
   "start_xy": [
    321386.7838736536,
    281795.1843352143
   ],
   "end_xy": [
    321381.96206839127,
    281796.5072817371
   ]
  },
  "min_10m": {
   "gradient_pct": -7.790440173411071,
   "start_distance_m": 1074.0,
   "end_distance_m": 1084.0,
   "midpoint_distance_m": 1079.0,
   "start_elevation_m": 285.5886286654817,
   "end_elevation_m": 284.80958464814057,
   "start_xy": [
    321441.9631222827,
    281791.1041587632
   ],
   "end_xy": [
    321432.3841170355,
    281788.23315719125
   ]
  },
  "min_20m": {
   "gradient_pct": -4.382170883332037,
   "start_distance_m": 3995.0,
   "end_distance_m": 4015.0,
   "midpoint_distance_m": 4005.0,
   "start_elevation_m": 428.450476696381,
   "end_elevation_m": 427.57404251971457,
   "start_xy": [
    318818.0692962715,
    282861.7399121475
   ],
   "end_xy": [
    318799.5852350137,
    282869.3779374727
   ]
  },
  "min_25m": {
   "gradient_pct": -4.029162800045242,
   "start_distance_m": 4000.0,
   "end_distance_m": 4025.0,
   "midpoint_distance_m": 4012.5,
   "start_elevation_m": 428.3323545267767,
   "end_elevation_m": 427.3250638267654,
   "start_xy": [
    318813.44842226105,
    282863.6497609508
   ],
   "end_xy": [
    318790.354042437,
    282873.216554198
   ]
  },
  "min_50m": {
   "gradient_pct": -3.122344959439488,
   "start_distance_m": 3983.0,
   "end_distance_m": 4033.0,
   "midpoint_distance_m": 4008.0,
   "start_elevation_m": 428.734734385691,
   "end_elevation_m": 427.17356190597127,
   "start_xy": [
    318829.15960432566,
    282857.1567847918
   ],
   "end_xy": [
    318784.27009574755,
    282878.405334786
   ]
  },
  "min_100m": {
   "gradient_pct": -1.6424649693367428,
   "start_distance_m": 3974.0,
   "end_distance_m": 4074.0,
   "midpoint_distance_m": 4024.0,
   "start_elevation_m": 428.7546183391769,
   "end_elevation_m": 427.11215336984014,
   "start_xy": [
    318837.4774964863,
    282853.7198293747
   ],
   "end_xy": [
    318753.3695988956,
    282905.3526717846
   ]
  }
 },
 "diagnostic_window_maxima": {
  "max_2m": {
   "gradient_pct": 40.570001154753754,
   "start_distance_m": 1099.0,
   "end_distance_m": 1101.0,
   "midpoint_distance_m": 1100.0,
   "start_elevation_m": 285.85802112661884,
   "end_elevation_m": 286.6694211497139,
   "start_xy": [
    321417.64417144284,
    281786.7201883306
   ],
   "end_xy": [
    321415.71538900456,
    281787.2491465797
   ]
  },
  "max_3m": {
   "gradient_pct": 40.58428528375089,
   "start_distance_m": 1099.0,
   "end_distance_m": 1102.0,
   "midpoint_distance_m": 1100.5,
   "start_elevation_m": 285.85802112661884,
   "end_elevation_m": 287.07554968513136,
   "start_xy": [
    321417.64417144284,
    281786.7201883306
   ],
   "end_xy": [
    321414.7509148895,
    281787.51332389045
   ]
  }
 },
 "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": 0.007,
   "obstruction_max_height_m": 7.43,
   "flagged_windows_m": []
  },
  "structure_suppression": {
   "masked_fraction": 0.001,
   "windows_resited": [
    2.0,
    3.0,
    10.0,
    20.0,
    25.0
   ],
   "windows_unresolved": []
  },
  "excluded_ranges_m": [
   [
    1161.0,
    1166.0
   ]
  ],
  "review": [],
  "extent": []
 },
 "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/SO1580.tif",
   "data/cache/england/bulk_dtm_1m/SO2080.tif"
  ],
  "calculated_at": "2026-08-19T18:26:43+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": [
   "SO1580.tif",
   "SO2080.tif"
  ],
  "climb_origin": "discovered",
  "notes": "Coarse pass: max 15.6% over 200 m (Terrain 50), gain 156.7 m over 2497 m way. EXTENDED by graph walk: +0 segment(s) at base, +4 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): clean-steep. AUTO-NAMED from gazetteer (hypothesis, unreviewed): was 'Discovered lane (52.4285, -3.1566)'.",
  "naming_note": "auto-named from gazetteer (hypothesis, unreviewed); discovered as 'Discovered lane (52.4285, -3.1566)'"
 },
 "area": {
  "place": "Quabbs",
  "county": "Shropshire"
 }
}