# GraphHopper Directions API > REST API for route optimization (vehicle routing, traveling salesman), route planning, turn-by-turn navigation, distance matrices, isochrones, geocoding, map matching, and location clustering. Built on OpenStreetMap and TomTom data. Base URL: https://graphhopper.com/api/1 ## Table of contents - [GraphHopper Directions API](https://docs.graphhopper.com/openapi.md)