# Features ## GET /collections/{collectionId}/items > Retrieve features in the feature collection ```json {"openapi":"3.0.1","info":{"title":"OS NGD API – Features","version":"v1.8.0"},"tags":[{"name":"Features","description":"Retrieve features"}],"servers":[{"url":"https://api.os.uk/features/ngd/ofa/v1"}],"security":[{"api-key":[],"api-key-header":[],"oauth2":[]}],"components":{"securitySchemes":{"api-key":{"type":"apiKey","name":"key","in":"query"}},"schemas":{"FeatureCollectionResponse":{"type":"object","properties":{"type":{"type":"string"},"links":{"type":"array","items":{"$ref":"#/components/schemas/Link"}},"timeStamp":{"type":"string","format":"date-time"},"features":{"type":"array","items":{"$ref":"#/components/schemas/Feature"}}}},"Link":{"type":"object","properties":{"href":{"type":"string","format":"url"},"rel":{"type":"string"},"type":{"type":"string"},"title":{"type":"string"}}},"Feature":{"type":"object","properties":{"id":{"type":"string"},"type":{"type":"string"},"geometry":{"$ref":"#/components/schemas/Geometry"},"properties":{"type":"object","additionalProperties":{"type":"object"}}}},"Geometry":{"type":"object","properties":{"type":{"type":"string"},"coordinates":{"type":"array","items":{"$ref":"#/components/schemas/Coordinate"}}}},"Coordinate":{"type":"object","properties":{"x":{"type":"number","format":"double"},"y":{"type":"number","format":"double"}}}}},"paths":{"/collections/{collectionId}/items":{"get":{"tags":["Features"],"summary":"Retrieve features in the feature collection","operationId":"getItems","parameters":[{"name":"collectionId","in":"path","description":"A known collection ID.","required":true,"schema":{"type":"string","enum":["asu-gbpcd-postcodeunitarea-1","asu-gbpcd-postcodeunitpoint-1","bld-fts-building-1","bld-fts-building-2","bld-fts-building-3","bld-fts-building-4","bld-fts-buildingaccesslocation-1","bld-fts-buildingline-1","bld-fts-buildingpart-1","bld-fts-buildingpart-2","gnm-fts-crowdsourcednamepoint-1","gnm-fts-namedarea-1","gnm-fts-namedpoint-1","gnm-fts-namedroadjunction-1","lnd-fts-land-1","lnd-fts-land-2","lnd-fts-land-3","lnd-fts-landform-1","lnd-fts-landformline-1","lnd-fts-landformpoint-1","lnd-fts-landpoint-1","lus-fts-site-1","lus-fts-site-2","lus-fts-siteaccesslocation-1","lus-fts-siteaccesslocation-2","lus-fts-siteroutingpoint-1","str-fts-compoundstructure-1","str-fts-compoundstructure-2","str-fts-compoundstructure-3","str-fts-fieldboundary-1","str-fts-structure-1","str-fts-structure-2","str-fts-structure-3","str-fts-structureline-1","str-fts-structurepoint-1","trn-fts-cartographicraildetail-1","trn-fts-rail-1","trn-fts-rail-2","trn-fts-rail-3","trn-fts-roadline-1","trn-fts-roadtrackorpath-1","trn-fts-roadtrackorpath-2","trn-fts-roadtrackorpath-3","trn-fts-streetlight-1","trn-ntwk-buslane-1","trn-ntwk-connectinglink-1","trn-ntwk-connectingnode-1","trn-ntwk-cyclelane-1","trn-ntwk-ferrylink-1","trn-ntwk-ferrynode-1","trn-ntwk-ferryterminal-1","trn-ntwk-path-1","trn-ntwk-pathlink-1","trn-ntwk-pathlink-2","trn-ntwk-pathlink-3","trn-ntwk-pathnode-1","trn-ntwk-pavementlink-1","trn-ntwk-railwaylink-1","trn-ntwk-railwaylinkset-1","trn-ntwk-railwaynode-1","trn-ntwk-road-1","trn-ntwk-roadjunction-1","trn-ntwk-roadlink-1","trn-ntwk-roadlink-2","trn-ntwk-roadlink-3","trn-ntwk-roadlink-4","trn-ntwk-roadlink-5","trn-ntwk-roadnode-1","trn-ntwk-street-1","trn-ntwk-tramonroad-1","trn-rami-averageandindicativespeed-1","trn-rami-highwaydedication-1","trn-rami-maintenancearea-1","trn-rami-maintenanceline-1","trn-rami-maintenancepoint-1","trn-rami-reinstatementarea-1","trn-rami-reinstatementline-1","trn-rami-reinstatementpoint-1","trn-rami-restriction-1","trn-rami-routinghazard-1","trn-rami-routingstructure-1","trn-rami-specialdesignationarea-1","trn-rami-specialdesignationline-1","trn-rami-specialdesignationpoint-1","wtr-fts-intertidalline-1","wtr-fts-tidalboundary-1","wtr-fts-water-1","wtr-fts-water-2","wtr-fts-water-3","wtr-fts-waterpoint-1","wtr-ntwk-waterlink-1","wtr-ntwk-waterlink-2","wtr-ntwk-waterlinkset-1","wtr-ntwk-waternode-1"]}},{"name":"bbox","in":"query","description":"The optional bbox parameter specifies a supported bounding box. Only features that have a geometry that intersects the bounding box are selected. The bounding box is provided as four comma-separated numbers: The default coordinate reference system of the values is WGS 84 longitude/latitude (http://www.opengis.net/def/crs/OGC/1.3/CRS84) unless a different coordinate reference system is specified in the parameter `bbox-crs`.","style":"form","explode":false,"schema":{"maxItems":6,"minItems":4,"type":"array","items":{"type":"number"}}},{"name":"bbox-crs","in":"query","description":"The coordinate reference system of the `bbox` parameter. It must be a 2D coordinate reference system supported by the collection. Default is WGS84 longitude/latitude (http://www.opengis.net/def/crs/OGC/1.3/CRS84).","schema":{"type":"string","enum":["http://www.opengis.net/def/crs/OGC/1.3/CRS84","http://www.opengis.net/def/crs/EPSG/0/27700","http://www.opengis.net/def/crs/EPSG/0/4326","http://www.opengis.net/def/crs/EPSG/0/3857"]}},{"name":"crs","in":"query","description":"The coordinate reference system of the response geometries. It must be a coordinate reference system supported by the collection. Default is WGS84 longitude/latitude (http://www.opengis.net/def/crs/OGC/1.3/CRS84).","schema":{"type":"string","enum":["http://www.opengis.net/def/crs/OGC/1.3/CRS84","http://www.opengis.net/def/crs/EPSG/0/27700","http://www.opengis.net/def/crs/EPSG/0/4326","http://www.opengis.net/def/crs/EPSG/0/3857","http://www.opengis.net/def/crs/EPSG/0/7405"]}},{"name":"datetime","in":"query","description":"Either a local date, a date-time with UTC time zone (Z) or an open or closed interval. Open ranges in time intervals at the start or end are supported using a double-dot (..) or an empty string for the start/end. Date and time expressions adhere to RFC 3339. Examples:Selects features that have a temporal property that intersects the value of the parameter.","style":"form","schema":{"type":"string"}},{"name":"limit","in":"query","description":"The optional limit parameter limits the number of items that are presented in the response document. Minimum = 1. Maximum = 100. Default = 100.","style":"form","schema":{"maximum":100,"minimum":1,"type":"integer"}},{"name":"offset","in":"query","description":"The optional offset parameter skips past the specified number of features in the collection. Minimum = 0. Default = 0.","schema":{"minimum":0,"type":"integer"}},{"name":"filter","in":"query","description":"The optional filter parameter is a filter expression in CQL format which is applied when retrieving resources to determine which resources are included in a result set.","schema":{"type":"string"}},{"name":"filter-crs","in":"query","description":"Specify which of the supported CRSs to use to encode geometric values in a filter expression. It must be a 2D coordinate reference system supported by the collection. Default is WGS84 longitude/latitude (http://www.opengis.net/def/crs/OGC/1.3/CRS84).","schema":{"type":"string","enum":["http://www.opengis.net/def/crs/OGC/1.3/CRS84","http://www.opengis.net/def/crs/EPSG/0/27700","http://www.opengis.net/def/crs/EPSG/0/4326","http://www.opengis.net/def/crs/EPSG/0/3857"]}},{"name":"filter-lang","in":"query","description":"The optional filter-lang parameter is the specific language used for the filter parameter. Default = cql-text","schema":{"type":"string","enum":["cql-text"]}}],"responses":{"200":{"description":"A list of features in a feature collection.","content":{"application/geo+json":{"schema":{"$ref":"#/components/schemas/FeatureCollectionResponse"}}}},"400":{"description":"The items request is not supported. Please refer to documentation for examples."},"404":{"description":"Collection '{collectionId}' is not a supported Collection. Please refer to the documentation for a list of supported Collections."},"405":{"description":"The HTTP method requested is not supported. This endpoint only supports 'GET' requests."},"406":{"description":"A request header value was not supported."},"504":{"description":"The request has timed out. Please check the service availability dashboard: https://osdatahub.os.uk/serviceStatus ."}}}}}} ``` --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.os.uk/os-apis/accessing-os-apis/os-ngd-api-features/technical-specification/features.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.