{ "ocl_version": "0.1.0", "name": "Gwytherin to Oerfa", "slug": "discovered-lane-53-1242-3-7104", "ladder": [ { "window_m": 2.0, "max_gradient_pct": 39.183674713260075, "diagnostic": true, "flags": [ "structure_excluded" ], "start_distance_m": 1071.0, "end_distance_m": 1073.0, "start_elevation_m": 360.06181212655036, "end_elevation_m": 360.84548562081557, "min_gradient_pct": -40.08686946098692, "suppressed_max_gradient_pct": 69.14053961920104, "suppressed_location_m": [ 302.0, 304.0 ] }, { "window_m": 3.0, "max_gradient_pct": 36.06378183223834, "diagnostic": true, "flags": [ "structure_excluded" ], "start_distance_m": 1071.0, "end_distance_m": 1074.0, "start_elevation_m": 360.06181212655036, "end_elevation_m": 361.1437255815175, "min_gradient_pct": -28.21907380916855, "suppressed_max_gradient_pct": 62.99090939839024, "suppressed_location_m": [ 302.0, 305.0 ] }, { "window_m": 5.0, "max_gradient_pct": 28.655688194282902, "diagnostic": false, "flags": [ "structure_excluded" ], "start_distance_m": 1070.0, "end_distance_m": 1075.0, "start_elevation_m": 359.918632923026, "end_elevation_m": 361.35141733274014, "min_gradient_pct": -19.114442796037565, "suppressed_max_gradient_pct": 37.68848360732022, "suppressed_location_m": [ 302.0, 307.0 ] }, { "window_m": 10.0, "max_gradient_pct": 23.98522741893629, "diagnostic": false, "flags": [ "structure_excluded" ], "start_distance_m": 274.0, "end_distance_m": 284.0, "start_elevation_m": 254.7972710467529, "end_elevation_m": 257.19579378864654, "min_gradient_pct": -15.938649200232362, "suppressed_max_gradient_pct": 26.07269182140726, "suppressed_location_m": [ 295.0, 305.0 ] }, { "window_m": 20.0, "max_gradient_pct": 22.403015151275696, "diagnostic": false, "flags": [ "structure_excluded" ], "start_distance_m": 247.0, "end_distance_m": 267.0, "start_elevation_m": 249.49498113681824, "end_elevation_m": 253.97558416707338, "min_gradient_pct": -13.600870339332971, "suppressed_max_gradient_pct": 25.089904959307603, "suppressed_location_m": [ 285.0, 305.0 ] }, { "window_m": 25.0, "max_gradient_pct": 21.86944030047391, "diagnostic": false, "flags": [ "structure_excluded" ], "start_distance_m": 242.0, "end_distance_m": 267.0, "start_elevation_m": 248.5082240919549, "end_elevation_m": 253.97558416707338, "min_gradient_pct": -11.95312118269544, "suppressed_max_gradient_pct": 24.72726594162259, "suppressed_location_m": [ 280.0, 305.0 ] }, { "window_m": 50.0, "max_gradient_pct": 20.73449142573145, "diagnostic": false, "flags": [ "structure_excluded" ], "start_distance_m": 238.0, "end_distance_m": 288.0, "start_elevation_m": 247.68364688378495, "end_elevation_m": 258.05089259665067, "min_gradient_pct": -10.62676482790016, "suppressed_max_gradient_pct": 22.27779136355485, "suppressed_location_m": [ 255.0, 305.0 ] }, { "window_m": 100.0, "max_gradient_pct": 19.251148092048197, "diagnostic": false, "flags": [ "canopy_or_structure", "structure_excluded" ], "start_distance_m": 350.0, "end_distance_m": 450.0, "start_elevation_m": 266.82266820159725, "end_elevation_m": 286.07381629364545, "min_gradient_pct": -10.321407581371432, "suppressed_max_gradient_pct": 19.411877283354784, "suppressed_location_m": [ 209.0, 309.0 ] } ], "length_m": 5855.517693338912, "start_elevation_m": 235.6018947400812, "end_elevation_m": 383.6291261772153, "endpoint_gain_m": 148.0272314371341, "overall_gradient_pct": 2.527995630608821, "accumulated_ascent_m": 258.58499025853945, "window_maxima": { "max_5m": { "gradient_pct": 28.655688194282902, "start_distance_m": 1070.0, "end_distance_m": 1075.0, "midpoint_distance_m": 1072.5, "start_elevation_m": 359.918632923026, "end_elevation_m": 361.35141733274014, "start_xy": [ 286875.1819960862, 360245.1041870732 ], "end_xy": [ 286870.4299654148, 360243.5491293579 ] }, "max_10m": { "gradient_pct": 23.98522741893629, "start_distance_m": 274.0, "end_distance_m": 284.0, "midpoint_distance_m": 279.0, "start_elevation_m": 254.7972710467529, "end_elevation_m": 257.19579378864654, "start_xy": [ 287431.19683229504, 360784.5316477965 ], "end_xy": [ 287421.98613749223, 360780.63766509894 ] }, "max_20m": { "gradient_pct": 22.403015151275696, "start_distance_m": 247.0, "end_distance_m": 267.0, "midpoint_distance_m": 257.0, "start_elevation_m": 249.49498113681824, "end_elevation_m": 253.97558416707338, "start_xy": [ 287456.06570826273, 360795.04540108 ], "end_xy": [ 287437.64431865705, 360787.2574356848 ] }, "max_25m": { "gradient_pct": 21.86944030047391, "start_distance_m": 242.0, "end_distance_m": 267.0, "midpoint_distance_m": 254.5, "start_elevation_m": 248.5082240919549, "end_elevation_m": 253.97558416707338, "start_xy": [ 287460.67105566413, 360796.99239242874 ], "end_xy": [ 287437.64431865705, 360787.2574356848 ] }, "max_50m": { "gradient_pct": 20.73449142573145, "start_distance_m": 238.0, "end_distance_m": 288.0, "midpoint_distance_m": 263.0, "start_elevation_m": 247.68364688378495, "end_elevation_m": 258.05089259665067, "start_xy": [ 287464.35533358523, 360798.5499855078 ], "end_xy": [ 287418.3018595711, 360779.0800720199 ] }, "max_100m": { "gradient_pct": 19.251148092048197, "start_distance_m": 350.0, "end_distance_m": 450.0, "midpoint_distance_m": 400.0, "start_elevation_m": 266.82266820159725, "end_elevation_m": 286.07381629364545, "start_xy": [ 287364.0171432044, 360749.2340746584 ], "end_xy": [ 287285.346395028, 360690.91589283984 ] } }, "window_minima": { "min_5m": { "gradient_pct": -19.114442796037565, "start_distance_m": 2101.0, "end_distance_m": 2106.0, "midpoint_distance_m": 2103.5, "start_elevation_m": 373.756510779353, "end_elevation_m": 372.8007886395511, "start_xy": [ 286026.977755127, 359888.7419738403 ], "end_xy": [ 286022.1273436753, 359887.5280921537 ] }, "min_10m": { "gradient_pct": -15.938649200232362, "start_distance_m": 4640.0, "end_distance_m": 4650.0, "midpoint_distance_m": 4645.0, "start_elevation_m": 382.1910890917481, "end_elevation_m": 380.59722417172486, "start_xy": [ 284005.8089470437, 358984.5874130863 ], "end_xy": [ 283996.15535161586, 358981.9781803801 ] }, "min_20m": { "gradient_pct": -13.600870339332971, "start_distance_m": 4636.0, "end_distance_m": 4656.0, "midpoint_distance_m": 4646.0, "start_elevation_m": 382.4057210062989, "end_elevation_m": 379.6855469384323, "start_xy": [ 284009.6703852149, 358985.6311061688 ], "end_xy": [ 283990.3631943592, 358980.41264075635 ] }, "min_25m": { "gradient_pct": -11.95312118269544, "start_distance_m": 4907.0, "end_distance_m": 4932.0, "midpoint_distance_m": 4919.5, "start_elevation_m": 373.78020726688123, "end_elevation_m": 370.7919269712074, "start_xy": [ 283767.4845388275, 358912.8325776611 ], "end_xy": [ 283743.6661165132, 358907.41575729573 ] }, "min_50m": { "gradient_pct": -10.62676482790016, "start_distance_m": 4896.0, "end_distance_m": 4946.0, "midpoint_distance_m": 4921.0, "start_elevation_m": 374.70194334991777, "end_elevation_m": 369.3885609359677, "start_xy": [ 283778.44361973065, 358911.8846611258 ], "end_xy": [ 283732.8056721217, 358898.58112387836 ] }, "min_100m": { "gradient_pct": -10.321407581371432, "start_distance_m": 4896.0, "end_distance_m": 4996.0, "midpoint_distance_m": 4946.0, "start_elevation_m": 374.70194334991777, "end_elevation_m": 364.38053576854634, "start_xy": [ 283778.44361973065, 358911.8846611258 ], "end_xy": [ 283703.8101478822, 358858.74175461486 ] } }, "diagnostic_window_maxima": { "max_2m": { "gradient_pct": 39.183674713260075, "start_distance_m": 1071.0, "end_distance_m": 1073.0, "midpoint_distance_m": 1072.0, "start_elevation_m": 360.06181212655036, "end_elevation_m": 360.84548562081557, "start_xy": [ 286874.2315899519, 360244.79317553015 ], "end_xy": [ 286872.33077768335, 360244.17115244403 ] }, "max_3m": { "gradient_pct": 36.06378183223834, "start_distance_m": 1071.0, "end_distance_m": 1074.0, "midpoint_distance_m": 1072.5, "start_elevation_m": 360.06181212655036, "end_elevation_m": 361.1437255815175, "start_xy": [ 286874.2315899519, 360244.79317553015 ], "end_xy": [ 286871.38037154905, 360243.860140901 ] } }, "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": 0.047, "obstruction_max_height_m": 16.06, "flagged_windows_m": [ 100 ] }, "structure_suppression": { "masked_fraction": 0.002, "windows_resited": [ 2.0, 3.0, 5.0, 10.0, 20.0, 25.0, 50.0, 100.0 ], "windows_unresolved": [] }, "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/wales/dtm_1m/wg_del_11_283358_20210302dtm.tif", "data/cache/wales/dtm_1m/wg_del_11_283359_20210302dtm.tif", "data/cache/wales/dtm_1m/wg_del_11_283360_20210302dtm.tif", "data/cache/wales/dtm_1m/wg_del_11_283361_20210302dtm.tif", "data/cache/wales/dtm_1m/wg_del_11_284358_20210302dtm.tif", "data/cache/wales/dtm_1m/wg_del_11_284359_20210302dtm.tif", "data/cache/wales/dtm_1m/wg_del_11_284360_20210302dtm.tif", "data/cache/wales/dtm_1m/wg_del_11_284361_20210302dtm.tif", "data/cache/wales/dtm_1m/wg_del_11_285358_20210302dtm.tif", "data/cache/wales/dtm_1m/wg_del_11_285359_20210302dtm.tif", "data/cache/wales/dtm_1m/wg_del_11_285360_20210302dtm.tif", "data/cache/wales/dtm_1m/wg_del_11_285361_20210302dtm.tif", "data/cache/wales/dtm_1m/wg_del_11_286358_20210302dtm.tif", "data/cache/wales/dtm_1m/wg_del_11_286359_20210302dtm.tif", "data/cache/wales/dtm_1m/wg_del_11_286360_20210302dtm.tif", "data/cache/wales/dtm_1m/wg_del_11_286361_20210302dtm.tif", "data/cache/wales/dtm_1m/wg_del_11_287358_20210302dtm.tif", "data/cache/wales/dtm_1m/wg_del_11_287359_20210302dtm.tif", "data/cache/wales/dtm_1m/wg_del_11_287360_20210302dtm.tif", "data/cache/wales/dtm_1m/wg_del_11_287361_20210302dtm.tif" ], "calculated_at": "2026-08-12T00:50:22+00:00", "road_source": "OpenStreetMap (local PBF extract)", "road_attribution": "\u00a9 OpenStreetMap contributors, ODbL", "osm_pbf_path": "data/cache/pbf/wales-2026-08-11.osm.pbf", "osm_snapshot": "2026-08-10T20:21:40Z", "elevation_provider": "Welsh Government", "elevation_dataset": "Welsh Government LiDAR 1m DTM (2020-2023)", "elevation_licence": "Open Government Licence v3 \u2014 \u00a9 Crown copyright Welsh Government", "elevation_catalogue_layer": "geonode:welsh_government_lidar_tile_catalogue_2020_2023", "elevation_tile_ids": [ "wg_del_11_283358_20210302dtm.tif", "wg_del_11_283359_20210302dtm.tif", "wg_del_11_283360_20210302dtm.tif", "wg_del_11_283361_20210302dtm.tif", "wg_del_11_284358_20210302dtm.tif", "wg_del_11_284359_20210302dtm.tif", "wg_del_11_284360_20210302dtm.tif", "wg_del_11_284361_20210302dtm.tif", "wg_del_11_285358_20210302dtm.tif", "wg_del_11_285359_20210302dtm.tif", "wg_del_11_285360_20210302dtm.tif", "wg_del_11_285361_20210302dtm.tif", "wg_del_11_286358_20210302dtm.tif", "wg_del_11_286359_20210302dtm.tif", "wg_del_11_286360_20210302dtm.tif", "wg_del_11_286361_20210302dtm.tif", "wg_del_11_287358_20210302dtm.tif", "wg_del_11_287359_20210302dtm.tif", "wg_del_11_287360_20210302dtm.tif", "wg_del_11_287361_20210302dtm.tif" ], "elevation_capture_dates": [ "02-03-2021" ], "climb_origin": "discovered", "notes": "Coarse pass: max 18.1% over 200 m (Terrain 50), gain 121.2 m over 4841 m way. EXTENDED by graph walk: +1 segment(s) at base, +3 at top (stop: base=no_descending_continuation, top=no_ascending_continuation; min_avg=2.0%). Review before adopting.", "naming_note": "auto-named from gazetteer (hypothesis, unreviewed); discovered as 'Discovered lane (53.1242, -3.7104)'" }, "area": { "place": "Gwytherin", "county": "Conwy - Conwy" }, "reported_claims": [], "confidence": "B", "shape": { "ascent_concentration": 0.571, "concentration_window_frac": 0.25, "longest_pitch_10pct_m": 269.0, "shape_class": "stepped" } }