The Natchez Trace is an old road which links Mississippi and Tennesse. It's a scenic road and motorists are limited to 50mph with strict radar control (although I've never seen any troopers out there, I guess just the mention of them is enough to keep people in line).
The Trace also has a rather sad history. It was part of the Trail of Tears, when Native Americans were "relocated" from their lands in the east into the open spaces of the west.
Today it makes for a nice drive, there are no billboards or advertisements to mar the natural beauty of the flora and fauna that call the Trace home.