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Diagnostic use only: never a headline or ranking value.", "quality_summary": { "overhead_obstruction": { "obstruction_threshold_m": 2.0, "obstructed_fraction": 0.057, "obstruction_max_height_m": 20.72, "flagged_windows_m": [ 5, 10, 20 ] }, "review": [], "extent": [ "may_start_earlier" ] }, "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_18_285223_20211201dtm.tif", "data/cache/wales/dtm_1m/wg_del_18_285224_20211201dtm.tif", "data/cache/wales/dtm_1m/wg_del_18_285225_20211201dtm.tif", "data/cache/wales/dtm_1m/wg_del_18_285226_20211201dtm.tif", "data/cache/wales/dtm_1m/wg_del_18_285227_20211201dtm.tif", "data/cache/wales/dtm_1m/wg_del_18_286223_20211201dtm.tif", "data/cache/wales/dtm_1m/wg_del_18_286224_20211201dtm.tif", "data/cache/wales/dtm_1m/wg_del_18_286225_20211201dtm.tif", "data/cache/wales/dtm_1m/wg_del_18_286226_20211201dtm.tif", "data/cache/wales/dtm_1m/wg_del_18_286227_20211201dtm.tif", "data/cache/wales/dtm_1m/wg_del_18_287223_20211201dtm.tif", "data/cache/wales/dtm_1m/wg_del_18_287224_20211201dtm.tif", "data/cache/wales/dtm_1m/wg_del_18_287225_20211201dtm.tif", "data/cache/wales/dtm_1m/wg_del_18_287226_20211201dtm.tif", "data/cache/wales/dtm_1m/wg_del_18_287227_20211201dtm.tif", "data/cache/wales/dtm_1m/wg_del_20_285222_20220112dtm.tif", "data/cache/wales/dtm_1m/wg_del_20_286222_20220112dtm.tif", "data/cache/wales/dtm_1m/wg_del_20_287222_20220112dtm.tif", "data/cache/wales/dtm_1m/wg_del_21_285220_20220113dtm.tif", "data/cache/wales/dtm_1m/wg_del_21_285221_20220113dtm.tif", "data/cache/wales/dtm_1m/wg_del_21_286220_20220113dtm.tif", "data/cache/wales/dtm_1m/wg_del_21_286221_20220113dtm.tif", "data/cache/wales/dtm_1m/wg_del_21_287220_20220113dtm.tif", "data/cache/wales/dtm_1m/wg_del_21_287221_20220113dtm.tif" ], "calculated_at": "2026-08-12T02:02:14+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_18_285223_20211201dtm.tif", "wg_del_18_285224_20211201dtm.tif", "wg_del_18_285225_20211201dtm.tif", "wg_del_18_285226_20211201dtm.tif", "wg_del_18_285227_20211201dtm.tif", "wg_del_18_286223_20211201dtm.tif", "wg_del_18_286224_20211201dtm.tif", "wg_del_18_286225_20211201dtm.tif", "wg_del_18_286226_20211201dtm.tif", "wg_del_18_286227_20211201dtm.tif", "wg_del_18_287223_20211201dtm.tif", "wg_del_18_287224_20211201dtm.tif", "wg_del_18_287225_20211201dtm.tif", "wg_del_18_287226_20211201dtm.tif", "wg_del_18_287227_20211201dtm.tif", "wg_del_20_285222_20220112dtm.tif", "wg_del_20_286222_20220112dtm.tif", "wg_del_20_287222_20220112dtm.tif", "wg_del_21_285220_20220113dtm.tif", "wg_del_21_285221_20220113dtm.tif", "wg_del_21_286220_20220113dtm.tif", "wg_del_21_286221_20220113dtm.tif", "wg_del_21_287220_20220113dtm.tif", "wg_del_21_287221_20220113dtm.tif" ], "elevation_capture_dates": [ "01-12-2021", "02-12-2021", "12-01-2022", "13-01-2022" ], "climb_origin": "discovered", "notes": "Coarse pass: max 10.0% over 200 m (Terrain 50), gain 110.5 m over 7682 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." }, "area": { "place": "Cwm Nantypistyll", "county": "Powys - Powys" }, "reported_claims": [], "confidence": "B", "shape": { "ascent_concentration": 0.405, "concentration_window_frac": 0.25, "longest_pitch_10pct_m": 102.0, "shape_class": "sustained" } }