If you love history, the Atlanta History Center is a great place to visit. Their Civil War exhibit is extremely comprehensive and could take hours to go through.
The mansion is also worth visiting and I loved our tour guide as she was extremely knowledgeable on the history of the house and the owners. I would recommend going during Spring/Summer to take full advantage of the outdoor trail and get to see the trees and flowers.
It's a great value for the price. If you are NOT into history that much, then you can still get some enjoyment out of it, but definitely not worth it as much.
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