On a previous article called "OpenStreetMap to GeoJSON", I explained how to extract Polygons from OSM using an online tool provided by from OSM France. And, on this article, I’ll explain how do that yourself directly using the OSM API and Python.

This also explains the basic concepts I used to write the osmexp tool, to export OSM elements into GeoJSON from the command-line.

Use OpenStreetMap as your repository of geometries, and export them in the more convenient GeoJSON format. This technique only works with geometries with area (Polygon and MultiPolygon), points and lines break the exporting tool used here.