I have spent a few days in Charleston, it is a nice place...but had friends there.
The Battery is like a sea front esplanade good to walk along, there is a fancy pineapple fountain there and many statues and old guns.
Fort Sumter is where the first shots of the US Civil War were fired, do on a boat tour. Interesting.
Patriots Point has an old Aircraft Carrier with planes on it, can walk nearly everywhere on it.
Many Southern Plantation type estates around the area and lots of old fancy houses in the city area.
Many churches and old buildings as well.
They have a decent museum too.
Savannah has similar fancy houses and plantations and also visit Chipewa Square, where Forest Gump was filmed waiting for the bus, and the church where the feather floats down is nearby as well.
Saw the square and did a general trolley tour and left...to go to Charleston.