MapSource is the complete tool for managing your GARMIN GPS. MapSource provides geographic data on a CD-ROM, which augments the information already on your GARMIN GPS base map. With MapSource you can view existing waypoints, routes and tracks on the graphic map or quickly create new waypoints with a click of mouse. Editing and managing your waypoints is made easy with MapSource.??MapSource United States Waterways & Lights shows U.S. inland cartography with shoreline detail of lakes, reservoirs, waterways, rivers, boat ramps, dams, facilities and danger areas and contains detailed U.S. map with cities, towns, highways, major local roads and interstates for all 50 states. United States Waterways & Lights displays nautical navigation aids of lights, buoys, sound signals and day beacons. In addition, it provides enhanced coastline detail, including thousands of small islands plus wrecks, obstructions and other hazards.