It depends on what kind of experience you are looking for. The Battles of Milton, Hovers Gap, Liberty Gap, Shelbyville& Nashville are all there within easy driving distance of Nashville. Fortress Rosecrans, & Forts Grainger, Henry, Donelson & Defiance are worth a look. If you are into historic houses, there are many CW era homes to tour. Cruising the river to Fort Donelson is eye opening. The Signal Corps Fort Negley, Fort Grainger, Works at Triune & Fort Transit are a very different & surprising CW story.
If you are looking for something in particular, please contact me.