This site provides free replacement maps for Garmin Nüvi series devices. The maps will also work on handheld Garmin devices (eTrex, Oregon, Dakota, Colorado, Montana, Colorado, GPSMAP 62) and the older Garmin StreetPilot devices if the device has an SD Card slot.
The maps are created using map data provided the OpenStreetMap project, a wikipedia-style site for collecting accurate map information. Like all maps, the maps provided here might have small errors. Everyone is encouraged to fix any problems they might encounter directly in OpenStreetMap using the user friendly iD map editor.
The maps on this site are refreshed every week so that everybody can benefit from fixes and updates without too much delay.