Extracting country borders as vector data from OpenStreetMap

Question

I want to download country borders as vector data from OpenStreetMap. The best would be in a common vector geodata format like GeoJSON that can be used e.g. in QGIS. I there a simple way to do this?

Answer 1

To download country borders from OpenStreetMap, you can use overpass-turbo.eu. I used the following expression:

[out:json][timeout:25];
relation[boundary=administrative][admin_level=2]["name:en"=Switzerland];
out geom;

Here's a direct link to the query (example country: Switzerland).

Replace the value after "name:en"= with the English name of your country or use name= to query it using the official (short) country name. Don't forget to insert quotes if the name contains spaces or special characters.

You can get the data as GeoJSON via Export > GeoJSON Download. When you load the layer into QGIS, only load the polygons.

A note on country borders including territorial waters: If your country includes a coastline to international waters (maritime borders), the national territory in OSM includes the territorial waters (usually 12 nautical miles from the low-tide coastline). To query only the landmass you might need a workaround when using OSM data. In some countries, downloading all level 4 administrative areas might work. Here's an example for Italy:

[out:json][timeout:25];
{{geocodeArea:Italy}};
relation[admin_level=4][boundary=administrative]["ISO3166-2"~"IT-"](area);
out geom;

Here's a direct link to the query

"ISO3166-2" is used here because without a unique country identifier parts of neighboring countries might be included due to inaccuracies.

Dissolve the layer to one Polygon/MultiPolygon in QGIS to reduce data volume.

However, this does not work for all countries either because no admin level exists that covers only the landmass or because level 4 administrative units also include territorial waters (e.g. Germany).