Owners of Garmin GPS units will be interested to know about two web sites offering free map and trail software created by “community mappers”.

GPS File Depot is a rich resource worth checking out. Dozens of free topo maps and some street maps are available for download; with maps for Arizona, California, New Mexico, to name just a very few. I downloaded the Arizona Topo Map onto my PC and used Garmin MapSource® software to install the map onto the micro-SD card in my eTrex Vista® HCx. The 24k topo map software came up and displayed as expected. It will be interesting to put it to use in the field.

In addition to the map downloads at GPS File Depot, you will also find several interesting tutorials, including a series describing how to create your own Garmin compatible maps.

MapSource® screen shot of Arizona Topo Map

Also worth a visit is the web page for Southwest Trails, a fascinating project devoted to creating transparent trail overlays for Garmin GPS units. Quoting from the web site: “In short, Southwest Trails is a transparent map overlay that you can put on your map-enabled Garmin GPS receiver. This allows you to see, and follow, trails using whatever maps you normally would on your GPS...be it topo maps, City Navigator, or any other sort of map that you have on your GPS.”

Both sites hint at a tantalizing future in which users and enthusiasts not only create GPS-ready topo maps, but also fill them in with up-to-date trail detail that is otherwise very difficult to come by. Looks like this future has already arrived!