The Coosa Backcountry Trail is a massive 39.4-mile singletrack loop that starts near Vogel State Park (and has a spur trail that runs to Vogel). The loop runs through the Sosebee Cove Scenic Area, heads up to Coosa Bald, runs with the Duncan Ridge Trail for a distance, and also runs through the Blood Mountain Wilderness. There's also a spur trail branching off that joins with the Appalachian Trail. Consequently, the Coosa Backcountry Trail can function as a connection from Vogel State Park to the AT, and from the AT to the Duncan Ridge Trail. With this variety of combinations available, you could backpack this area for weeks and not have exhausted all of the possibilities!
See Google Maps location. Located near Vogel State Park
http://www.tripleblaze.com/trail.php?c=3&i=6972