I attend college in Florida. A friend and I are planning on roadtripping back home together once school gets out in early May. So far, we're planning on driving up to Charleston on I-95 to visit the U.S.S. Yorktown, then taking I-75 through the Smokies before cutting over to Mammoth Cave and then taking I-65 the rest of the way to Chicago. We have no time constraints and our only objection is cost - we're planning on spending most of our nights in a tent in order to save money. Does anyone have any suggestions regarding things to stop and see on our way?