Understanding Overpass, the API of OpenStreetMap

If you want to use spatial data from OpenStreetMap[1], one way to get it is via Overpass[2], a read-only API of the OpenStreetMap database. While the API is extremely flexible, its unique language, Overpass QL is not very intuitive. This article takes a very simple query and dissects it into its smallest pieces. This will help you understand (and write) such queries.

An overpass at the junction of the M1 and M7 motorways in Hungary, 1968. FORTEPAN/UVATERV. Creative Commons CC-BY-SA-3.0