I'd center in Franklin, with more in Spring Hill, and have optional tours to Nashville and Stones River--and I think we could ask to see the Forrest Boyhood Home which is nearby. There are a ton of neat entertainment options in Franklin (I might be able to prevail on a friend from high school for some entertainment, too. You might look him up--Lee Roy Parnell).
In Franklin: Carter House, Lotz House, Carnton are great. Tom Cartwright is with the Lotz House now. Carnton takes at least half a day--and the Battlefield Trust has done a nice job surrounding. Winstead Hill is a MUST to figure out the battle. There are also related things, since the battle was in town--the Cotton Gin site, which was saved from that awful Pizza Hut existence...I'm sure
@EricAJacobson could fill us in on more since the last time I was there in fall 2017. I never have enough time at the Carter House, and Rippavilla in Spring Hill is good, too. I can see a full Friday-Saturday-Sunday doing Franklin/Spring Hill, with enough side trips to make folks from far away happy...and Nashville is an extremely easy airport to navigate!
LOL, as
@luinrina and I discussed, you can even drive past THIS on the Interstate and see for yourself how hideous it is....
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