Geo::OSM::Tiles provides functions for calculating the path to a map tile at
 OpenStreetMap out of geographic coordinates. The path of a tile at OSM has
 the form $zoom/$tilex/$tiley.png. The numbering scheme is documented in the
 OSM wiki at http://wiki.openstreetmap.org/wiki/Slippy_map_tilenames .
 .
 The package also contains the downloadosmtiles script that allows one to
 conveniently download OSM map tiles from a given OSM permalink URL.