{ "ocl_version": "0.1.0", "name": "Primrose Hill", "slug": "primrose-hill-llanbadarn", "ladder": [ { "window_m": 2.0, "max_gradient_pct": 17.991745862193298, "diagnostic": true, "flags": [], "start_distance_m": 283.0, "end_distance_m": 285.0, "start_elevation_m": 34.10577808897179, "end_elevation_m": 34.465613006215655, "min_gradient_pct": -1.1681501119229054 }, { "window_m": 3.0, "max_gradient_pct": 16.379938626072033, "diagnostic": true, "flags": [], "start_distance_m": 291.0, "end_distance_m": 294.0, "start_elevation_m": 35.26722229352974, "end_elevation_m": 35.7586204523119, "min_gradient_pct": -1.2344082075346208 }, { "window_m": 5.0, "max_gradient_pct": 15.771802113097948, "diagnostic": false, "flags": [], "start_distance_m": 299.0, "end_distance_m": 304.0, "start_elevation_m": 36.464441105228836, "end_elevation_m": 37.253031210883734, "min_gradient_pct": 0.5282323506277109 }, { "window_m": 10.0, "max_gradient_pct": 15.340058658520732, "diagnostic": false, "flags": [], "start_distance_m": 291.0, "end_distance_m": 301.0, "start_elevation_m": 35.26722229352974, "end_elevation_m": 36.801228159381814, "min_gradient_pct": 1.1166286415871873 }, { "window_m": 20.0, "max_gradient_pct": 14.964420977709167, "diagnostic": false, "flags": [], "start_distance_m": 283.0, "end_distance_m": 303.0, "start_elevation_m": 34.10577808897179, "end_elevation_m": 37.09866228451362, "min_gradient_pct": 1.3803396077051655 }, { "window_m": 25.0, "max_gradient_pct": 14.679739389703828, "diagnostic": false, "flags": [], "start_distance_m": 283.0, "end_distance_m": 308.0, "start_elevation_m": 34.10577808897179, "end_elevation_m": 37.775712936397746, "min_gradient_pct": 1.3567118513104788 }, { "window_m": 50.0, "max_gradient_pct": 13.372050947349315, "diagnostic": false, "flags": [], "start_distance_m": 142.0, "end_distance_m": 192.0, "start_elevation_m": 20.20486864298869, "end_elevation_m": 26.890894116663347, "min_gradient_pct": 3.1177547784685022 }, { "window_m": 100.0, "max_gradient_pct": 12.28140286745166, "diagnostic": false, "flags": [], "start_distance_m": 109.0, "end_distance_m": 209.0, "start_elevation_m": 16.589852857300635, "end_elevation_m": 28.871255724752295, "min_gradient_pct": 5.719536976065749 } ], "shape": { "ascent_concentration": 0.363, "concentration_window_frac": 0.25, "longest_pitch_10pct_m": 94.0, "shape_class": "sustained" }, "length_m": 309.6243579966355, "start_elevation_m": 10.08921764540778, "end_elevation_m": 37.94569617188405, "endpoint_gain_m": 27.856478526476273, "overall_gradient_pct": 8.99686274901504, "accumulated_ascent_m": 27.90117328705799, "window_maxima": { "max_5m": { "gradient_pct": 15.771802113097948, "start_distance_m": 299.0, "end_distance_m": 304.0, "midpoint_distance_m": 301.5, "start_elevation_m": 36.464441105228836, "end_elevation_m": 37.253031210883734, "start_xy": [ 260124.77958555904, 281094.5738016757 ], "end_xy": [ 260129.7531393515, 281094.4038375474 ] }, "max_10m": { "gradient_pct": 15.340058658520732, "start_distance_m": 291.0, "end_distance_m": 301.0, "midpoint_distance_m": 296.0, "start_elevation_m": 35.26722229352974, "end_elevation_m": 36.801228159381814, "start_xy": [ 260117.03034469776, 281096.51496071933 ], "end_xy": [ 260126.76271165733, 281094.37773768377 ] }, "max_20m": { "gradient_pct": 14.964420977709167, "start_distance_m": 283.0, "end_distance_m": 303.0, "midpoint_distance_m": 293.0, "start_elevation_m": 34.10577808897179, "end_elevation_m": 37.09866228451362, "start_xy": [ 260109.4111816329, 281098.9538855216 ], "end_xy": [ 260128.76190135026, 281094.32081166346 ] }, "max_25m": { "gradient_pct": 14.679739389703828, "start_distance_m": 283.0, "end_distance_m": 308.0, "midpoint_distance_m": 295.5, "start_elevation_m": 34.10577808897179, "end_elevation_m": 37.775712936397746, "start_xy": [ 260109.4111816329, 281098.9538855216 ], "end_xy": [ 260133.61750267845, 281095.3610684178 ] }, "max_50m": { "gradient_pct": 13.372050947349315, "start_distance_m": 142.0, "end_distance_m": 192.0, "midpoint_distance_m": 167.0, "start_elevation_m": 20.20486864298869, "end_elevation_m": 26.890894116663347, "start_xy": [ 260030.6749373397, 281008.41834428534 ], "end_xy": [ 260044.15347318657, 281056.56737409305 ] }, "max_100m": { "gradient_pct": 12.28140286745166, "start_distance_m": 109.0, "end_distance_m": 209.0, "midpoint_distance_m": 159.0, "start_elevation_m": 16.589852857300635, "end_elevation_m": 28.871255724752295, "start_xy": [ 260019.5861733017, 280977.4024768563 ], "end_xy": [ 260050.68071866725, 281072.0946079659 ] } }, "window_minima": { "min_5m": { "gradient_pct": 0.5282323506277109, "start_distance_m": 41.0, "end_distance_m": 46.0, "midpoint_distance_m": 43.5, "start_elevation_m": 11.495907943093293, "end_elevation_m": 11.522319560624679, "start_xy": [ 260002.44419093945, 280915.20582288946 ], "end_xy": [ 260000.40880188765, 280919.77279030863 ] }, "min_10m": { "gradient_pct": 1.1166286415871873, "start_distance_m": 36.0, "end_distance_m": 46.0, "midpoint_distance_m": 41.0, "start_elevation_m": 11.41065669646596, "end_elevation_m": 11.522319560624679, "start_xy": [ 260004.47957999125, 280910.6388554703 ], "end_xy": [ 260000.40880188765, 280919.77279030863 ] }, "min_20m": { "gradient_pct": 1.3803396077051655, "start_distance_m": 26.0, "end_distance_m": 46.0, "midpoint_distance_m": 36.0, "start_elevation_m": 11.246251639083646, "end_elevation_m": 11.522319560624679, "start_xy": [ 260006.29687672885, 280900.87227151665 ], "end_xy": [ 260000.40880188765, 280919.77279030863 ] }, "min_25m": { "gradient_pct": 1.3567118513104788, "start_distance_m": 21.0, "end_distance_m": 46.0, "midpoint_distance_m": 33.5, "start_elevation_m": 11.183141597797059, "end_elevation_m": 11.522319560624679, "start_xy": [ 260006.9358376877, 280895.91326668777 ], "end_xy": [ 260000.40880188765, 280919.77279030863 ] }, "min_50m": { "gradient_pct": 3.1177547784685022, "start_distance_m": 1.0, "end_distance_m": 51.0, "midpoint_distance_m": 26.0, "start_elevation_m": 10.156298424685733, "end_elevation_m": 11.715175813919984, "start_xy": [ 260003.8337705857, 280876.2445894807 ], "end_xy": [ 259999.19134490564, 280924.58362705616 ] }, "min_100m": { "gradient_pct": 5.719536976065749, "start_distance_m": 0.0, "end_distance_m": 100.0, "midpoint_distance_m": 50.0, "start_elevation_m": 10.08921764540778, "end_elevation_m": 15.808754621473529, "start_xy": [ 260003.6475847352, 280875.26207493676 ], "end_xy": [ 260015.70294708855, 280969.28332947637 ] } }, "diagnostic_window_maxima": { "max_2m": { "gradient_pct": 17.991745862193298, "start_distance_m": 283.0, "end_distance_m": 285.0, "midpoint_distance_m": 284.0, "start_elevation_m": 34.10577808897179, "end_elevation_m": 34.465613006215655, "start_xy": [ 260109.4111816329, 281098.9538855216 ], "end_xy": [ 260111.3159723991, 281098.34415432106 ] }, "max_3m": { "gradient_pct": 16.379938626072033, "start_distance_m": 291.0, "end_distance_m": 294.0, "midpoint_distance_m": 292.5, "start_elevation_m": 35.26722229352974, "end_elevation_m": 35.7586204523119, "start_xy": [ 260117.03034469776, 281096.51496071933 ], "end_xy": [ 260119.88753084707, 281095.6003639185 ] } }, "diagnostic_note": "Windows <=3 m are at raster-noise scale (roughly +/-2 pp 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": 0.029, "obstruction_max_height_m": 2.73, "flagged_windows_m": [] }, "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/wales/dtm_1m/wg_del_23_260280_20220117dtm.tif", "data/cache/wales/dtm_1m/wg_del_23_260281_20220117dtm.tif", "data/cache/wales/dtm_1m/wg_del_29_259280_20220319dtm.tif", "data/cache/wales/dtm_1m/wg_del_29_259281_20220319dtm.tif" ], "calculated_at": "2026-08-12T14:32:39+00:00", "road_source": "OpenStreetMap (local PBF extract)", "road_attribution": "\u00a9 OpenStreetMap contributors, ODbL", "osm_ids": [ 379919473, 219140741, 68543978 ], "osm_versions": { "379919473": 3, "219140741": 8, "68543978": 11 }, "osm_timestamps": { "379919473": "2025-03-24 07:32:18+00:00", "219140741": "2026-01-28 20:50:33+00:00", "68543978": "2026-03-11 04:39:45+00:00" }, "osm_retrieved_at": "2026-08-12T14:32:39+00:00", "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_23_260280_20220117dtm.tif", "wg_del_23_260281_20220117dtm.tif", "wg_del_29_259280_20220319dtm.tif", "wg_del_29_259281_20220319dtm.tif" ], "elevation_capture_dates": [ "17-01-2022", "19-03-2022" ], "climb_origin": "named", "signed_gradient_pct": 12, "signed_source": "OSM incline tag (12%) on the upper way" }, "area": { "place": "Pwllhobi", "county": "Sir Ceredigion - Ceredigion" } }