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  "calculated_at": "2026-08-12T09:11:50+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",
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  "elevation_capture_dates": [
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  "climb_origin": "osm_incline",
  "notes": "Harlech, neighbour of Ffordd Pen Llech. EXTENDED by graph walk: +0 segment(s) at base, +6 at top (stop: base=no_descending_continuation, top=no_ascending_continuation; min_avg=2.0%). Review before adopting."
 },
 "area": {
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  "county": "Gwynedd - Gwynedd"
 },
 "reported_claims": [
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   "evidence_type": "mapper_estimate",
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   "retrieved_at": "2026-08-10",
   "credibility": "Unverified: tag history not yet checked; no sign photo sighted",
   "observed_via": "osm_tag_history"
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 ],
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  "shape_class": "sustained"
 }
}