{
  "schemaVersion": 1,
  "built": "2026-10-09",
  "retrieved": "2026-10-09",
  "sourceId": "london-boundary",
  "evidence": "derived",
  "sourceEvidence": "sourced",
  "source": "https://services1.arcgis.com/ESMARspQHYMw9BZ9/arcgis/rest/services/Regions_December_2024_Boundaries_EN_BFC/FeatureServer/0",
  "request": "https://services1.arcgis.com/ESMARspQHYMw9BZ9/arcgis/rest/services/Regions_December_2024_Boundaries_EN_BFC/FeatureServer/0/query?where=RGN24CD%3D%27E12000007%27&outFields=RGN24CD%2CRGN24NM&outSR=4326&returnGeometry=true&f=geojson",
  "license": "Open Government Licence v3.0",
  "licenceUrl": "https://www.ons.gov.uk/methodology/geography/licences",
  "attribution": "Source: Office for National Statistics licensed under the Open Government Licence v.3.0. Contains OS data \u00a9 Crown copyright and database right 2025.",
  "boundary": {
    "dataset": "Regions (December 2024) Boundaries EN BFC",
    "code": "E12000007",
    "name": "London",
    "bbox": [
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    ],
    "sha256": "79a5e6539164de53b219228193b247d0b25c6fdd0c6c00cdf2ae5188fea8b485",
    "bytes": 1319515,
    "vertices": 34901,
    "geometryAreaSqKm": 1573.8564583389973
  },
  "overview": {
    "bbox": [
      -1.05,
      51.0,
      0.9,
      52.05
    ],
    "crs": "EPSG:4326",
    "northUp": true
  },
  "asset": {
    "file": "london-boundary-display-mask.png",
    "href": "/media/city-twin/london-boundary-display-mask.png",
    "format": "PNG",
    "mode": "L",
    "bands": 1,
    "bitsPerBand": 8,
    "lossless": true,
    "width": 1024,
    "height": 878,
    "bytes": 3033,
    "sha256": "10c2b24995a79fa6760736c34372916ecf9c217c27b3b87a67973347028a06cd",
    "bbox": [
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      0.9,
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    ],
    "crs": "EPSG:4326",
    "northUp": true,
    "transform": [
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      0,
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    "displayPixelM": [
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    "insideSamples": 91107,
    "totalSamples": 899072,
    "channel": "red",
    "values": {
      "inside": 255,
      "outside": 0
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  },
  "outline": null,
  "method": "Full-resolution official ONS polygon, including its holes, rasterised on the exact shared wide EPSG:4326 display grid with Pillow polygon fill. No buffer or source geometry simplification. One-band, binary 0/255 PNG, lossless decoded values verified.",
  "purpose": "Declared display area of interest: Greater London. Exterior photographic context may be quietened; dated analyses are shown only within this area.",
  "limits": "A display mask, not an observation, a sensor footprint or a QA mask. Its display pixels are approximately 134 m and do not imply cadastral precision. Every source/QA gap inside London remains transparent; this mask never fills or changes an observation. No extra outline band is supplied."
}