GeoTiler is a library to create maps using tiles from a map provider. The main goal of the library is to enable a programmer to create maps using tiles downloaded from OpenStreetMap, Stamen or other map provider. The maps can be used by interactive applications or to create data analysis graphs. The code is based on Python port of Modest Maps project [1][2], which is licensed under BSD license. All subsequent changes are licensed under GPL v3 license. [1] http://modestmaps.com/ [2] https://github.com/stamen/modestmaps-py