OpenStreetMap Overpass API
The Overpass API is a read-only database engine for complex geospatial queries against the OSM dataset. Accepts Overpass QL or XML queries and returns results in XML, JSON, GeoJSON, or CSV. Safe usage: under 10,000 queries/day and under 1 GB/day. Python SDKs include overpass, overpy, and OSMPythonTools; JavaScript SDKs include query-overpass and overpass-ts.