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Diagnostic use only: never a headline or ranking value.", "quality_summary": { "overhead_obstruction": { "obstruction_threshold_m": 2.0, "obstructed_fraction": 0.304, "obstruction_max_height_m": 29.48, "flagged_windows_m": [ 2, 3, 5, 10, 20, 25, 50, 100 ] }, "structure_suppression": { "masked_fraction": 0.014, "windows_resited": [ 2.0, 3.0, 5.0, 10.0, 20.0, 25.0, 50.0 ], "windows_unresolved": [] }, "no_bench_suppression": { "masked_fraction": 0.046, "windows_resited": [ 2.0, 3.0, 5.0, 10.0, 20.0, 25.0, 50.0 ], "windows_unresolved": [] }, "excluded_ranges_m": [ [ 832.0, 842.0 ], [ 900.0, 946.0 ], [ 1317.0, 1322.0 ], [ 1560.0, 1600.0 ], [ 1740.0, 1880.0 ], [ 4147.0, 4152.0 ] ], "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_8_307312_20210222dtm.tif", "data/cache/wales/dtm_1m/wg_del_8_307313_20210222dtm.tif", "data/cache/wales/dtm_1m/wg_del_8_307314_20210222dtm.tif", "data/cache/wales/dtm_1m/wg_del_8_307315_20210222dtm.tif", "data/cache/wales/dtm_1m/wg_del_8_307316_20210222dtm.tif", "data/cache/wales/dtm_1m/wg_del_8_308312_20210222dtm.tif", "data/cache/wales/dtm_1m/wg_del_8_308313_20210222dtm.tif", "data/cache/wales/dtm_1m/wg_del_8_308314_20210222dtm.tif", "data/cache/wales/dtm_1m/wg_del_8_308315_20210222dtm.tif", "data/cache/wales/dtm_1m/wg_del_8_308316_20210222dtm.tif", "data/cache/wales/dtm_1m/wg_del_8_309312_20210222dtm.tif", "data/cache/wales/dtm_1m/wg_del_8_309313_20210222dtm.tif", "data/cache/wales/dtm_1m/wg_del_8_309314_20210222dtm.tif", "data/cache/wales/dtm_1m/wg_del_8_309315_20210222dtm.tif", "data/cache/wales/dtm_1m/wg_del_8_309316_20210222dtm.tif", "data/cache/wales/dtm_1m/wg_del_8_310312_20210222dtm.tif", "data/cache/wales/dtm_1m/wg_del_8_310313_20210222dtm.tif", "data/cache/wales/dtm_1m/wg_del_8_310314_20210222dtm.tif", "data/cache/wales/dtm_1m/wg_del_8_310315_20210222dtm.tif", "data/cache/wales/dtm_1m/wg_del_8_310316_20210222dtm.tif" ], "calculated_at": "2026-08-12T09:08:59+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_8_307312_20210222dtm.tif", "wg_del_8_307313_20210222dtm.tif", "wg_del_8_307314_20210222dtm.tif", "wg_del_8_307315_20210222dtm.tif", "wg_del_8_307316_20210222dtm.tif", "wg_del_8_308312_20210222dtm.tif", "wg_del_8_308313_20210222dtm.tif", "wg_del_8_308314_20210222dtm.tif", "wg_del_8_308315_20210222dtm.tif", "wg_del_8_308316_20210222dtm.tif", "wg_del_8_309312_20210222dtm.tif", "wg_del_8_309313_20210222dtm.tif", "wg_del_8_309314_20210222dtm.tif", "wg_del_8_309315_20210222dtm.tif", "wg_del_8_309316_20210222dtm.tif", "wg_del_8_310312_20210222dtm.tif", "wg_del_8_310313_20210222dtm.tif", "wg_del_8_310314_20210222dtm.tif", "wg_del_8_310315_20210222dtm.tif", "wg_del_8_310316_20210222dtm.tif" ], "elevation_capture_dates": [ "22-02-2021" ], "climb_origin": "discovered", "notes": "Coarse pass: max 18.0% over 200 m (Terrain 50), gain 119.0 m over 4567 m way. EXTENDED by graph walk: +0 segment(s) at base, +1 at top (stop: base=no_descending_continuation, top=no_ascending_continuation; min_avg=2.0%). Review before adopting. ADOPTED (notable slice 2026-08-11): qualified-steep. AUTO-NAMED from gazetteer (hypothesis, unreviewed): was 'Discovered lane (52.7180, -3.3470)'.", "naming_note": "auto-named from gazetteer (hypothesis, unreviewed); discovered as 'Discovered lane (52.7180, -3.3470)'" }, "area": { "place": "Cwm Einion", "county": "Powys - Powys" }, "reported_claims": [], "confidence": "B", "shape": { "ascent_concentration": 0.474, "concentration_window_frac": 0.25, "longest_pitch_10pct_m": 346.0, "shape_class": "stepped" } }