# By Intersecting Polygon

For this request, you must send a `POST` request. It is formatted as follows (as an example Javascript `fetch` request):

```
const requestBody = {
    key : "your_api_key",
    maps : "<category>",
    polygon_geojson : featureCollection
};

fetch("https://native-land.ca/api/index.php", {
    method : "POST",
    body : JSON.stringify(requestBody)
})
```

The `requestBody` that you send must have all three parameters to function. `maps` must be a comma-separated string of `territories`, `languages`, and/or `treaties`.

An example `polygon_geojson` would be:

```
{
  “type”: “FeatureCollection”,
  “features”: [
    {
      “type”: “Feature”,
      “properties”: {},
      “geometry”: {
        “type”: “Polygon”,
        “coordinates”: [
          [
            [
              -105.556640625,
              58.17070248348609
            ],
            [
              -107.09472656249999,
              57.11238500793404
            ],
            [
              -104.853515625,
              56.145549500679074
            ],
            [
              -98.6572265625,
              56.70450561416937
            ],
            [
              -97.55859375,
              57.89149735271034
            ],
            [
              -99.8876953125,
              58.49369382056807
            ],
            [
              -103.7548828125,
              58.768200159239576
            ],
            [
              -105.556640625,
              58.17070248348609
            ]
          ]
        ]
      }
    }
  ]
}
```

**Please avoid sending extremely details or complex polygons, as this slows down the response and puts an extra load on the server.**

We are using PostgreSQL with PostGIS to speed up your spatial queries.