Defining Polygon Shapes in GeoJSON

In geometry, a polygon is a closed two-dimensional shape with straight sides. It is formed by connecting multiple line segments called edges. A polygon consists of vertices (corner points) and edges that connect these vertices. The edges do not cross each other, and the last vertex is connected to the first vertex, creating a closed shape. Polygons can have different numbers of sides, ranging from three to infinity.

A polygon shape represents a specific instance of a polygon. It defines the exact coordinates of its vertices, allowing for the precise representation of the polygon on a two-dimensional plane. Polygons are commonly used to represent various geographic features such as land boundaries, city boundaries, lakes, or countries.

The below image shows a polygon shape which represents the postal code area 3273 in the Netherlands visualized in kepler.gl

Postal code area 3273 in the Netherlands

The above shape, when defined in a GeoJSON format looks, a bit, like the JSON structure below. the “a bit” part is because we did not show all coordinates pairs is a full set of 895 vertices, which is inconvient to display in a blogpost.

{
  "type": "Feature",
  "properties": {
    "postalCode": "3273"
  },
  "geometry": {
    "type": "Polygon",
    "coordinates": [
      [

        [4.437842656838879, 51.79863262764456],
        [4.437848550343165…