I believe technically it was South Carolina. Check "The Official Military Atlas of the Civil War" Plate 5, map 4, Plate 133, map 3. Today it would be Jones Island, South Carolina. It is part of Tybee Island National Wildlife Refuge almost due east of Savannah.

I hope this helps.

Respectfully,

Gerald D. Hodge, Jr.
M.A. Military History - Civil War Concentration
Research - Preservation
Historian: 39th Georgia Volunteer Infantry Regiment