Topography

According to the United States Census Bureau, the city has a total area of 343.0 km² (132 sq mi). 341.2 km² (132 sq mi) of it is land and 1.8 km² (1 sq mi) of it is water. The total area is 0.51% water. At about 1,050 feet (320 m) above mean sea level (the airport is 1,010 feet (308 m)), Atlanta sits atop a ridge south of the Chattahoochee River. Atlanta has the highest average elevation of any major city east of Denver.

The Eastern Continental Divide line enters Atlanta from the south, proceeding to downtown. From downtown, the divide line runs eastward along DeKalb Avenue and the CSX rail lines through Decatur. Rainwater that falls on the south and east side runs eventually into the Atlantic Ocean while rainwater on the north and west side of the divide runs into the Gulf of Mexico.

The latter is via the Chattahoochee River, part of the ACF River Basin, and from which Atlanta and many of its neighbors draw most of their water. Being at the far northwestern edge of the city, much of the river's natural habitat is still preserved, in part by the Chattahoochee River National Recreation Area. Downstream however, excessive water use during droughts and pollution during floods has been a source of contention and legal battles with neighboring states Alabama and Florida.