The built-in map covers the globe, but has very little detail. The easiest way to add contour maps for hiking is to buy them, but you can also download free, open-source maps. Try a web search for "free eTrex maps" or something like that. I'm using a free detailed contour map of the NW US and am happy with it. It works both in the unit and in Garmin's Base Camp program. Some maps give some pretty idiotic driving directions, though. Experiment.