This wiki is no longer maintained as of April 2012. Existing users may update articles, however user registration is disabled.
Geonames is an open source database of geographical names and associated information such as population and elevation.
Geonames contains over eight million geographical names for 7.5 million unique features worldwide, with 2.8 million populated places.
Users can tag a location on the map giving it coordinates and then input a new name and categorise it. Features are categorized into one of nine feature classes and further subcategorized out of 645 feature codes. These locations are then searchable and displayed on a zoomable slippy map. The project has 'ambassadors' in many countries around the world.
Data sets are available for download and all work is licensed under a Creative Commons Attribution 3.0 License.
Tim Berners Lee commented: This is a tremendous set of data you have.'