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  "calculated_at": "2026-08-15T05:02:49+00:00",
  "road_source": "OpenStreetMap (local PBF extract)",
  "road_attribution": "\u00a9 OpenStreetMap contributors, ODbL",
  "osm_pbf_path": "data/cache/pbf/england-2026-08-12-roads.osm.pbf",
  "osm_snapshot": "2026-08-12T20:21:46Z",
  "elevation_provider": "Environment Agency",
  "elevation_dataset": "EA LIDAR Composite DTM 1m (2022)",
  "elevation_licence": "Open Government Licence v3 \u2014 \u00a9 Environment Agency",
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  "notes": "Coarse pass: max 8.2% over 200 m (Terrain 50), gain 35.4 m over 915 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.",
  "naming_note": "auto-named from gazetteer (hypothesis, unreviewed); discovered as 'Discovered lane (51.0552, -3.7364)'"
 },
 "area": {
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  "county": "Devon"
 }
}