nashville
Visit the Gibson Store---even if you don't like them, it's most impressive.
By all means visit Mammoth Cave---you can spend days in there on guided trips alone---It's not a "typical" cave---and it is Mammoth. It's a halc an hour north of Bowling Green<KY. While there, check out the Corvette Museum and factory---both interesting visits, and the cleanest car factory I've ever been in. Memphis is not too far, either, and it's the home of some great music, too.