{
  "retrieved": "2026-10-02",
  "sources": [
    {
      "provider": "AreaCity / Amap",
      "url": "https://github.com/xiangyuecn/AreaCity-JsSpider-StatsGov/releases/tag/2025.251231.260403",
      "version": "2025.251231.260403",
      "released": "2026-04-03",
      "coordinateSystem": "GCJ-02",
      "license": "MIT",
      "archiveSHA256": "675c3e9b8dec6444994d3ef53259a145304f6a957db8a5e601e55c0b9e61e21a",
      "features": 2,
      "codes": [
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        659012
      ]
    },
    {
      "provider": "National Land Surveying and Mapping Center (NLSC), Ministry of the Interior",
      "url": "https://data.gov.tw/dataset/7442",
      "download": "https://maps.nlsc.gov.tw/download/縣市界線(TWD97經緯度).zip",
      "sourceFile": "COUNTY_MOI_1090820.shp",
      "coordinateSystem": "TWD97 geographic, converted to WGS84",
      "license": "Taiwan Open Government Data License 1.0",
      "licenseURL": "https://data.gov.tw/license",
      "archiveSHA256": "0c6fca34a92b92ef3e9a41957e403cb89e814bb64942ca7c7e51c746f913d49d",
      "features": 22
    },
    {
      "provider": "Hong Kong Home Affairs Department",
      "url": "https://data.gov.hk/en-data/dataset/hk-had-json1-hong-kong-administrative-boundaries",
      "download": "https://www.had.gov.hk/psi/hong-kong-administrative-boundaries/hksar_18_district_boundary.json",
      "sourceFile": "hk-districts-official.json",
      "sha256": "ab2123b5a48c2e39e29ce594a0c51590cf6081922ab2c5c14ff78338b788f760",
      "features": 18,
      "coordinateSystem": "WGS84",
      "licenseURL": "https://data.gov.hk/en/terms-and-conditions"
    },
    {
      "provider": "Hong Kong Lands Department",
      "url": "https://portal.csdi.gov.hk/csdi-webpage/metadata/landsd_rcd_1637221775627_85634/html",
      "download": "https://portal.csdi.gov.hk/server/rest/services/common/landsd_rcd_1637221775627_85634/MapServer/7/query?where=TYPE%3D%27SEF%27&outFields=CLASS%2CTYPE&outSR=4326&f=geojson",
      "sourceFile": "hk-sea.json",
      "sha256": "b4c2ec9d610dfc310cf455227ad539baebdc138005b9df7d648ca76bc668d03a",
      "coordinateSystem": "WGS84",
      "scale": "1:50,000",
      "processing": "Sea polygons erased from official district jurisdictions; all coastline vertices retained.",
      "licenseURL": "https://data.gov.hk/en/terms-and-conditions"
    },
    {
      "provider": "Macao government online map",
      "url": "https://webmap.gis.gov.mo/MapGIS/index.html",
      "download": "https://webmap.gis.gov.mo/arcgis/rest/services/ThematicMap/Freg_stats/MapServer/0/query?where=1%3D1&outFields=*&returnGeometry=true&f=json",
      "sourceFile": "mo-parish-native.json",
      "sha256": "05b529e6948c1adaac16586562139e24f1b86685d3af6dd1b53d371b8b3e73d8",
      "features": 11,
      "coordinateSystem": "Macau Grid converted to WGS84 using official Annex I six-parameter transformation",
      "coordinateReference": "https://www.dscc.gov.mo/files/geographical_level_point/PORT/Macaucoord_2009_web_PT_v201702.pdf",
      "processing": "Seven parish polygons and four other areas, retaining all source vertices."
    },
    {
      "provider": "DataV Zhuhai districts",
      "download": "https://geo.datav.aliyun.com/areas_v3/bound/440400_full.json",
      "sourceFile": "zhuhai-districts.json",
      "sha256": "80f0d1d5141d197b3a96b699876547246491fe8e89d36fd8bb3c93adef3a9193",
      "coordinateSystem": "GCJ-02, numerically converted to WGS84",
      "processing": "Districts dissolved into one city outline; used only in the coastal coverage window beside Macau."
    },
    {
      "provider": "OpenStreetMap Zhuhai port coastline",
      "url": "https://www.openstreetmap.org/way/230560846",
      "download": "https://api.openstreetmap.org/api/0.6/map?bbox=113.57,22.195,113.599,22.224",
      "sourceFile": "zhuhai-port-land.json",
      "sha256": "fe136a726e9dcef8308a8eaa7da1e2e624ecb392652573bdb2429989bc7b4357",
      "coordinateSystem": "WGS84",
      "retrieved": "2026-10-02",
      "ways": [
        "230560846",
        "1227614103",
        "1227614101"
      ],
      "license": "ODbL 1.0",
      "licenseURL": "https://www.openstreetmap.org/copyright",
      "reusableDataset": "data/zhuhai-port-land.json",
      "processing": "Connected coastline ways form the physical port island. Macau government jurisdiction is retained and erased from the Zhuhai portion."
    },
    {
      "provider": "OpenStreetMap Wanzai coastline",
      "url": "https://www.openstreetmap.org/way/667085646",
      "sourceFile": "wanzai-coastline.json",
      "sha256": "af042922e304559f6ec60c7805d60bbd2445df13db0a3b8107c50c1167a54f51",
      "coordinateSystem": "WGS84",
      "retrieved": "2026-10-02",
      "ways": [
        "667085646",
        "915139248"
      ],
      "license": "ODbL 1.0",
      "licenseURL": "https://www.openstreetmap.org/copyright",
      "reusableDataset": "data/wanzai-coastline.json",
      "coverageWindow": [
        113.515,
        22.17,
        113.5365,
        22.216
      ],
      "processing": "Physical shoreline replaces the coarse land fill beside Macau. Closure edges are inland or outside the replacement window."
    },
    {
      "provider": "OpenStreetMap Chongming Island",
      "url": "https://www.openstreetmap.org/relation/3292765",
      "download": "https://api.openstreetmap.org/api/0.6/relation/3292765/full",
      "osmRelation": "3292765",
      "osmVersion": 16,
      "vertices": 3685,
      "sourceFile": "chongming-island.json",
      "sha256": "65a2bb2b61066bf3842016a3a7019d115ba9f5baee86ccce2816b24d50da433b",
      "coordinateSystem": "WGS84",
      "retrieved": "2026-10-02",
      "license": "ODbL 1.0",
      "licenseURL": "https://www.openstreetmap.org/copyright",
      "reusableDataset": "data/chongming-island.json",
      "sourceVersions": "data/chongming-source-versions.json",
      "processing": "Connected original node references; every source shoreline vertex retained without simplification. Physical land is partitioned by the existing administrative boundary."
    },
    {
      "provider": "OpenStreetMap Chongming North Branch mainland bank",
      "url": "https://www.openstreetmap.org/way/10004875",
      "osmWays": [
        "243633362",
        "8013710",
        "370342705",
        "8002514",
        "9997283",
        "10004875",
        "10014769",
        "9982816",
        "9983315",
        "245609508",
        "885089575",
        "9987270",
        "683628707",
        "10014561"
      ],
      "vertices": 2748,
      "sourceFile": "chongming-north-bank.json",
      "sha256": "1cc7ab8c444a6ded6f3035ae4487ec1c06bbbc7f035bdef0da3d9848a744e00b",
      "coordinateSystem": "WGS84",
      "retrieved": "2026-10-02",
      "license": "ODbL 1.0",
      "licenseURL": "https://www.openstreetmap.org/copyright",
      "reusableDataset": "data/chongming-north-bank.json",
      "sourceVersions": "data/chongming-source-versions.json",
      "processing": "Connected original node references; every source shoreline vertex retained without simplification. Physical land is partitioned by the existing administrative boundary."
    },
    {
      "provider": "OpenStreetMap Shenzhen physical shoreline",
      "query": "way[\"natural\"=\"coastline\"](22.36,113.68,22.91,114.70);out meta geom;",
      "endpoint": "https://overpass-api.de/api/interpreter",
      "coordinateSystem": "WGS84",
      "timestamp": "2026-10-04T22:04:43Z",
      "license": "ODbL 1.0",
      "licenseUrl": "https://www.openstreetmap.org/copyright",
      "definition": "https://wiki.openstreetmap.org/wiki/Tag:natural%3Dcoastline",
      "sourceDownload": "data/shenzhen-coast-source.bin",
      "sourceCompression": "gzip JSON",
      "sha256": "91a7640d9df8a9c7c6f8e5a5260f4df2c6da9c4ac59e133931b85260931a1cbf",
      "ways": 1312,
      "vertices": 58219,
      "landPolygons": 886,
      "url": "https://www.openstreetmap.org/copyright",
      "sourceFile": "shenzhen-land.json",
      "reusableDataset": "data/shenzhen-land.json",
      "sourceVersions": "data/shenzhen-coast-source.bin",
      "processing": "Physical land mask assembled from directed original coastline ways. Shenzhen city and its nine mapped districts are clipped to this mask; inland jurisdiction data is retained. No shoreline simplification or image tracing."
    },
    {
      "provider": "OpenStreetMap Shanghai and Zhoushan physical shorelines",
      "timestamp": "2026-10-04T23:40:34Z",
      "coordinateSystem": "WGS84",
      "query": "way[\"natural\"=\"coastline\"](29.3,120.6,32.2,123.6);out meta geom;",
      "endpoint": "https://overpass-api.de/api/interpreter",
      "license": "ODbL 1.0",
      "licenseUrl": "https://www.openstreetmap.org/copyright",
      "definition": "https://wiki.openstreetmap.org/wiki/Tag:natural%3Dcoastline",
      "sourceDownload": "data/east-coast-source.bin",
      "sourceCompression": "gzip JSON",
      "sha256": "ed33a715e5c439a6570e28c42d144feadcbf62991e9ce92ceb214d76cbfaffdc",
      "ways": 1690,
      "vertices": 122970,
      "landPolygons": 1222,
      "processingBounds": [
        120.6,
        29.3,
        123.6,
        32.2
      ],
      "sourceFile": "east-coast-land.bin",
      "reusableDataset": "data/east-coast-land.bin",
      "compression": "gzip JSON",
      "sourceVersions": "data/east-coast-source.bin",
      "processing": "Original directed OpenStreetMap coastlines define physical land without simplification. Only Shanghai and Zhoushan display coverage changes. Existing shared administrative edges and Chongming’s Shanghai/Jiangsu split remain fixed. Whole physical islands replace coarse components when one existing jurisdiction or an unambiguous official island checkpoint establishes ownership. Islands shared with other jurisdictions retain the existing administrative partition. Source bounding-box edges never become display shorelines."
    },
    {
      "provider": "OpenStreetMap Zhuhai, Guangzhou and Huizhou physical shorelines",
      "query": "way[\"natural\"=\"coastline\"](21.65,112.95,24.10,115.60);out meta geom;",
      "endpoint": "https://overpass-api.de/api/interpreter",
      "coordinateSystem": "WGS84",
      "timestamp": "2026-10-04T23:02:51Z",
      "license": "ODbL 1.0",
      "licenseUrl": "https://www.openstreetmap.org/copyright",
      "definition": "https://wiki.openstreetmap.org/wiki/Tag:natural%3Dcoastline",
      "sourceDownload": "data/pearl-coast-source.bin",
      "sourceCompression": "gzip JSON",
      "sha256": "9aaf90dfae9d1c842e7b1d90f9e10969f428b1c8258bf0a9fbb6816e9dae20ac",
      "ways": 3723,
      "vertices": 177741,
      "landPolygons": 2640,
      "processingBounds": [
        112.95,
        21.65,
        115.6,
        24.1
      ],
      "sourceFile": "pearl-coast-land.bin",
      "reusableDataset": "data/pearl-coast-land.bin",
      "compression": "gzip JSON",
      "sourceVersions": "data/pearl-coast-source.bin",
      "processing": "Retain original directed OpenStreetMap coastline vertices. Project only exterior mainland coast segments within 2.5 km; shared administrative edges and junctions remain fixed. Clip physical land and replace entire islands where existing jurisdiction or an unambiguous national catalogue match establishes ownership. Catalogue coordinates have 0.1 arcminute precision; a rounding cell is accepted only when it intersects one physical island. Retain partitions on islands shared by jurisdictions. Hengqin uses the physical land mask minus unchanged Macau government jurisdictions; the reviewed port island uses its existing physical shoreline. No rectangular coastal preservation window is applied. Apply the same parent extent to Guangzhou districts; only Nansha coastal additions are filled."
    },
    {
      "timestamp": "2026-10-05T00:29:25Z",
      "provider": "OpenStreetMap coastal wetland and harbor-access geometry",
      "coordinateSystem": "WGS84",
      "sha256": "3011702e2330d3de823acea3e76d561f8df507fd69573174a72679e5477d30ba",
      "landwardEdges": [
        {
          "id": 1107703029,
          "start": 1,
          "end": 3,
          "reverse": true,
          "version": 1
        },
        {
          "id": 1107703027,
          "start": 1,
          "end": 5,
          "version": 1
        },
        {
          "id": 985635390,
          "start": 5,
          "end": 9,
          "version": 3
        },
        {
          "id": 985635389,
          "start": 26,
          "end": 28,
          "reverse": true,
          "version": 3
        },
        {
          "id": 1107742533,
          "start": 1,
          "end": 2,
          "version": 1
        },
        {
          "id": 1107742537,
          "start": 22,
          "end": 23,
          "reverse": true,
          "version": 1
        }
      ],
      "coastWay": {
        "id": 842632375,
        "version": 4
      },
      "northCoastWay": {
        "id": 662581919,
        "version": 5,
        "endIndex": 257
      },
      "structureWays": [
        826453672,
        829094532
      ],
      "excludedNorthSpur": {
        "way": 662581919,
        "startIndex": 262,
        "endIndex": 287
      },
      "excludedTidalDikes": [
        826365004,
        826365005,
        826365006,
        1107742531
      ],
      "license": "ODbL 1.0",
      "licenseUrl": "https://www.openstreetmap.org/copyright",
      "reference": "https://swj.sh.gov.cn/shshyglswzx-xwdt/20220718/91cf7191971d444d98f2771f5645caf2.html",
      "imagery": "EOxCloudless Sentinel-2 2025, same alignment as the satellite layer",
      "processing": "Nanhui mainland display follows the landward edge of the mapped coastal wetlands along the seawall. Exposed tidal flats and tidal training dikes are excluded from the land fill. Narrow offshore breakwaters are omitted from the administrative land silhouette; their source geometry is retained for reference. Only Pudong display geometry changes; administrative inland boundaries and Dishui Lake remain unchanged.",
      "shoreline": [
        [
          121.9206044,
          31.0938657
        ],
        [
          121.891055,
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        ],
        [
          121.8921819,
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        ],
        [
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        ],
        [
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        ],
        [
          121.9337258,
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        ],
        [
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        ],
        [
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        ],
        [
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        ],
        [
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        ],
        [
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        ],
        [
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        ],
        [
          121.9384575,
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        ],
        [
          121.9395411,
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        ],
        [
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        ],
        [
          121.9498622,
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        ],
        [
          121.9536173,
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        ],
        [
          121.9538694,
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        ],
        [
          121.9645291,
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        ],
        [
          121.9646264,
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        ],
        [
          121.9733766,
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        ],
        [
          121.974155,
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        ]
      ],
      "sourceFile": "nanhui-shore-source.bin",
      "reusableDataset": "data/nanhui-shore-source.bin",
      "compression": "gzip JSON"
    }
  ],
  "missing": [
    {
      "adcode": 659013,
      "name": "草湖市",
      "english": "Caohu",
      "reason": "Established after AreaCity release; no reusable polygon boundary found in checked sources."
    }
  ],
  "processing": {
    "simplification": false,
    "zhuhai": "Detailed DataV district union replaces coastal coverage within [113.48,22.08,113.61,22.26]. The entire old port island is replaced by the connected OpenStreetMap shoreline; Macau government polygons retain jurisdiction.",
    "displayCoordinateSystem": "WGS84",
    "mainland": "DataV and AreaCity GCJ-02 coordinates numerically converted to WGS84, retaining every source vertex before government overlays.",
    "coordinateReference": "https://help.aliyun.com/en/datav/datav-7-0/user-guide/map-data-format-1",
    "xinjiang": "New cities clipped to the existing detailed Xinjiang extent, then erased from the older prefectures. Coincident overlay vertices joined within 1e-10 degrees.",
    "taiwan": "Official county/city polygons replace the coarse Taiwan outline. Overlapping older Fujian island components are replaced as whole components to prevent residual coastlines.",
    "sar": "Official Hong Kong land-clipped districts and Macau parish/area polygons replace previous SAR geometry after legacy gap repair. Their land polygons are erased from neighboring Guangdong to prevent overlapping fills.",
    "replacedFujianIslandParts": [
      "350100-1",
      "350100-4",
      "350100-5",
      "350100-8",
      "350100-17",
      "350100-18",
      "350100-22",
      "350100-23",
      "350300-11",
      "350500-1",
      "350500-2"
    ],
    "retainedOtherProvinceBordersAfterCoordinateConversion": 26,
    "macau": "Macau shared parish edges are reconciled with 1e-8 degree vertex snapping and a 0.5 m sliver-gap threshold before coastline extraction. No simplification is applied; validation bounds boundary displacement to 0.5 m.",
    "chongming": "OpenStreetMap island relation 3292765 replaces only the main Chongming island. The existing Shanghai/Jiangsu administrative split is retained on the island. Connected north-bank coastline ways remove North Branch river water from Nantong within [121.10,31.42,122.05,31.93]. Changxing, Hengsha and all other subdivisions retain their previous geometry.",
    "shenzhen": "Only Shenzhen display coverage is clipped to detailed OpenStreetMap land; the Guangdong outline and shared line networks are derived from those polygons. Original administrative sources and Hong Kong polygons remain unchanged. This depicts physical land rather than offshore jurisdiction. Mean high-water coastline may differ from imagery tides and dates.",
    "shenzhenHongKong": "Copy the official Hong Kong land-border path between existing common junctions into Shenzhen. Project adjoining exterior district vertices onto the same path and retain all intervening official coordinates. Connected internal district junctions move with their exterior endpoint; coastlines and inland segments outside the reviewed seam retain their coordinates. Existing common land-border junctions between the Shenzhen River estuary and Sha Tau Kok. Coastal and estuary shorelines outside these junctions are preserved.",
    "pearlCoast": "Retain original directed OpenStreetMap coastline vertices. Project only exterior mainland coast segments within 2.5 km; shared administrative edges and junctions remain fixed. Clip physical land and replace entire islands where existing jurisdiction or an unambiguous national catalogue match establishes ownership. Catalogue coordinates have 0.1 arcminute precision; a rounding cell is accepted only when it intersects one physical island. Retain partitions on islands shared by jurisdictions. Hengqin uses the physical land mask minus unchanged Macau government jurisdictions; the reviewed port island uses its existing physical shoreline. No rectangular coastal preservation window is applied. Apply the same parent extent to Guangzhou districts; only Nansha coastal additions are filled.",
    "eastCoast": "Original directed OpenStreetMap coastlines define physical land without simplification. Only Shanghai and Zhoushan display coverage changes. Existing shared administrative edges and Chongming’s Shanghai/Jiangsu split remain fixed. Whole physical islands replace coarse components when one existing jurisdiction or an unambiguous official island checkpoint establishes ownership. Islands shared with other jurisdictions retain the existing administrative partition. Source bounding-box edges never become display shorelines.",
    "nanhuiShore": "Nanhui mainland display follows the landward edge of the mapped coastal wetlands along the seawall. Exposed tidal flats and tidal training dikes are excluded from the land fill. Narrow offshore breakwaters are omitted from the administrative land silhouette; their source geometry is retained for reference. Only Pudong display geometry changes; administrative inland boundaries and Dishui Lake remain unchanged.",
    "zhuhaiMacau": "Fill enclosed physical-land gaps at Gongbei between the existing Zhuhai polygon and the unchanged official Macau boundary. Only complete gap components inside the reviewed checkpoint extent are eligible; components reaching its edge, sea and adjacent reclamation are excluded. Retain the physical coastline and all Macau source coordinates."
  }
}