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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.",
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  "calculated_at": "2026-08-12T02:15:23+00:00",
  "road_source": "OpenStreetMap (local PBF extract)",
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  "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",
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  "climb_origin": "discovered",
  "notes": "Coarse pass: max 9.3% over 200 m (Terrain 50), gain 42.0 m over 829 m way. EXTENDED by graph walk: +1 segment(s) at base, +0 at top (stop: base=no_descending_continuation, top=no_ascending_continuation; min_avg=2.0%). Review before adopting. DEDUPE: absorbed 1 overlapping proposal(s): discovered-lane-53-0943-4-0634",
  "renamed": "2026-08-13: RENAMED per identification-certain policy: route-line 3 m from the Wikidata pass point; en+cy Wikipedia articles"
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  "place": "Bryant's Gully",
  "county": "Gwynedd - Gwynedd"
 },
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 "confidence": "A",
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}