Geonames (geonames.org/) provides a lot of data for geographic places. This includes coordinates and markings on a map, as well as other contextual information.
GN250 contains data from the German Federal Agency for Cartography and Geodesy. The entries are contextualized by a type, for example "Landschaft" (landscape).
The GND is the integrated authority file of the german Nationalbibliothek. It provides standardized data records concerning persons, corporate bodies, congresses, geographic entities, topics and works.