The rapids of the Savannah River, above Augusta, expose upturned metamorphic rocks at the edge of the Piedmont province. By resisting erosion, they gradually emerged above the easily eroded sediments of the Coastal Plain. The Savannah and Georgia's other major rivers tumble over rapids and falls as they cross the Piedmont. The boats and barges of colonial commerce could navigate no further upriver and had to be unloaded at the Fall Line. At the same time, the rapids were harnessed to power machinery and afford transportation using dams and canals. These steps left the rapids largely dry, but the rocks remain in place. This photo was taken just below the dam that feeds the Augusta Canal
, built in 1845 and today a National Heritage Area.
Several other Georgia cities were founded on the Fall Line: Columbus on the Chatahoochee River, Macon on the Ocmulgee, and Milledgeville on the Oconee. The Fall Line extends west into Alabama and north as far as New Jersey.