A:Answer The GPSMAP 64st comes with a built-in worldwide basemap with shaded relief, and comes preloaded with TOPO U.S. 100K maps that includes coverage or the full United States (including Alaska, Hawaii, and Puerto Rico). Although the worldwide basemap does include South America and Europe, it won't have nearly as much detail as the TOPO maps. Adding more maps is easy with our array of detailed topographic, marine and road maps. With 8 GB of onboard memory and microSD card slot, you can conveniently download TOPO 24K maps and hit the trail, plug in BlueChart g2 preloaded cards for a great day on the water or City Navigator NT map data for turn-by-turn routing on roads. Thanks! (KS)