The base unit does not have usable maps. You need to by a package that includes a map, buy the maps separately, or use OS maps. Garmin's maps are called CityNavigator and are available on CD, microSD card, or via download. The go for ~$100.
Info is on the Garmin website:
https://buy.garmin.com/shop/shop.do?cID=160&pID=112912
Edge 810 $500
- Edge 810
- Bike mount
- USB cable
- AC charger
- Manual
Edge 810 Performance and Navigation Bundle $700
- Edge 810
- Mounts (standard and out-front)
- Premium heart rate monitor
- Speed/cadence sensor
- Data card preloaded with City Navigator® for US, Canada and Puerto Rico street maps (maps on a preloaded data card cannot be copied or viewed on a computer)
- USB cable
- AC charger
- Manual