Garmin fenix is a tourist watch equipped with a GPS receiver. In published specification Garmin declared no support for maps, but watch has basic map and about 20MB free storage. There is possibility to install additional maps with Mapsource or MapInstall.
The presentation of the map is very limited. Small, black and white screen doesn't allow for many details. Zoom, pan or rotation of a map is slow. Maps had to be adapted for this device.
I have created maps basing on schema developed by GPS Maniak. Maps contain a limited set of features - forests, roads, villages. Compilation is optimized for size and speed.
Garmin has provided free programs for managing maps on PC - BaseCamp and Mapsorce. BaseCamp for Windows and Mac OS is available here:
Mapsource is available only for Windows. You can install update for Mapsource after installing BaseCamp:
Maps are divided into tiles up to 3.5MB size, you can load several selected tiles from PC to device. Easiest way to load maps is to use Mapsource, it allows for selecting tiles and transfer to fenix attached to USB. Mapsource creates file \Garmin\gmapsupp.img on device.
When using BaseCamp loading maps is supported by external program MapInstall. It works similar to Mapsource but creates file with name, that is not recognized by fenix. After transferring files to device you have to manually rename new img file to \Garmin\gmapsupp.img.
At the bottom of the page there is sample data for Sicily.