> For the complete documentation index, see [llms.txt](https://docs.os.uk/os-apis/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.os.uk/os-apis/accessing-os-apis/os-ngd-api-features/technical-specification/feature.md).

# Feature

## GET /collections/{collectionId}/items/{featureId}

> Retrieve a feature from the feature collection

```json
{"openapi":"3.0.1","info":{"title":"OS NGD API – Features","version":"v1.8.1"},"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":{"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/{featureId}":{"get":{"tags":["Features"],"summary":"Retrieve a feature from the feature collection","operationId":"getItemById","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":"featureId","in":"path","description":"A feature ID which is the identifier(id) for the feature.","required":true,"schema":{"type":"string"}},{"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"]}}],"responses":{"200":{"description":"A single feature in the feature collection.","content":{"application/geo+json":{"schema":{"$ref":"#/components/schemas/Feature"}}}},"400":{"description":"The feature request contains elements that are not supported. Please refer to documentation for examples."},"404":{"description":"The feature collection '{collectionId}' or feature with id:'{featureId}' could not be found. Please check it is a supported collection or feature."},"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 ."}}}}}}
```


---

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