The Flint River is a 344-mile-long river in the U.S. state of Georgia. The river drains 8,460 square miles of western Georgia, flowing south from the upper Piedmont region south of Atlanta to the wetlands of the Gulf Coastal Plain in the southwestern corner of the state. Along with the Apalachicola and the Chattahoochee rivers, it forms part of the ACF basin. In its u…The Flint River is a 344-mile-long river in the U.S. state of Georgia. The river drains 8,460 square miles of western Georgia, flowing south from the upper Piedmont region south of Atlanta to the wetlands of the Gulf Coastal Plain in the southwestern corner of the state. Along with the Apalachicola and the Chattahoochee rivers, it forms part of the ACF basin. In its upper course through the red hills of the Piedmont, it is considered especially scenic, flowing unimpeded for over 200 miles. Historically, it was also called the Thronateeska River.