Our daughter lived in Charleston for about 9 years, so we were there several times. I love just being in the downtown area. You are surrounded by history - you can feel it in the air. My DH was never bored. You can go to Fort Sumpter, browse the antique shops on King St. as well as all the restored home tours. Walking on places where George Washington walked was amazing to me. The city market is fascinating and just walking the cobbled streets that are over 200 years old and seeing the architecture. Magnolia Plantation has the most beautiful gardens. The restaurants have the most amazing food.
Charleston is just so entirely different from anything we have out here on the Plains.