The Swann Preserve is a lovely little nature preserve on the southside of Atlanta. It protects a small forest of mature trees along with a portion of the headwaters of the South River.
There is a PATH Foundation trail through the preserve with a bridge over the South River.
Atlanta is actually the headwaters for several rivers, even though it’s not in the mountains. This section of the South River is still fairly clear and not as polluted, unlike the section through Constitution Lakes.