{
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 "name": "Padarn Crescent",
 "slug": "padarn-crescent",
 "confidence": "A",
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   "observation_date": "2024-07",
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 "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": {
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   "obstructed_fraction": 0.014,
   "obstruction_max_height_m": 4.09,
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  "extent": [
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 },
 "provenance": {
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  "interpolation": "bilinear",
  "smoothing": "none",
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  "elevation_crs": "EPSG:27700",
  "elevation_resolution_m": 1.0,
  "elevation_tiles": [
   "data/cache/wales/dtm_1m/wg_del_29_259281_20220319dtm.tif"
  ],
  "calculated_at": "2026-08-20T23:51:17+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_29_259281_20220319dtm.tif"
  ],
  "elevation_capture_dates": [
   "19-03-2022"
  ],
  "climb_origin": "discovered",
  "notes": "ADOPTED 2026-08-20: sign-validated (Peter's Street View find; seeded from the sighting \u2014 the coarse pass misses short steep residentials, Terrain 50 smooths them under the seed bar). First route born via extend --openroads (100% OR-snapped). Measured max50 15.7% vs the posted 16%; shorter windows run above the sign (max25 19.3%, max5 22.2%). The Cefn Llan pattern, minus the sign upgrade.",
  "license": "ODbL-1.0",
  "license_url": "https://howsteep.org/licensing.html"
 }
}