GeoJSON

JavaScript Object Notation (JSON), and the terms object, name, value, array, and number, are defined in IETF RFC 4627 . The key words “MUST”, “MUST NOT”, “REQUIRED”, “SHALL”, “SHALL NOT”, “SHOULD”, “SHOULD NOT”, “RECOMMENDED”, “MAY”, and “OPTIONAL” in this document are to be interpreted as described in IETF RFC 2119 . The GeoJSON object must have a member with the name "type" . This member’s value is a string that determines the type of the GeoJSON object. A GeoJSON geometry object of any type other than "GeometryCollection" must have a member with the name "coordinates" . The value of the coordinates member is always an array. The structure for the elements in this array is determined by the type of geometry. For type "Point" , the "coordinates" member must be a single position. For type "Polygon" , the "coordinates" member must be an array of LinearRing coordinate arrays. For Polygons with multiple rings, the first must be the exterior ring and any others must be interior rings or holes. A GeoJSON object with the type "FeatureCollection" is a feature collection object. The default CRS is a geographic coordinate reference system, using the WGS84 datum, and with longitude and latitude units of decimal degrees. A non-null CRS object has two mandatory members: "type" and "properties" . The value of the type member must be a string, indicating the type of CRS object. A link object has one required member: "href" , and one optional member: "type" . The value of the required "href" member must be a dereferenceable URI. Each of the examples below represents a complete GeoJSON object. Note that unquoted whitespace is not significant in JSON. Whitespace is used in the examples to help illustrate the data structures, but is not required. Coordinates of a Polygon are an array of LinearRing coordinate arrays. The first element in the array represents the exterior ring. Any subsequent elements represent interior rings (or holes).