If you drive straight down US 23 out of Kingsport it'll turn into I-26 as it goes into Western NC, and you will quickly hit some absolutely spectacular country. If you detour over onto NC 209 south of Hot Springs NC (via NC 212), you will find yourself on one of the prettiest (twisty!) drives in the east for about two hours, all the way down to I-40. (But don't tell anybody!)
You can then take I-40 west to I-81 and back up to 23 to get back to Kingsport a different way, maybe faster maybe not.
There's also some nice country north of Kingsport especially up around Wise and Big Stone Gap, VA, but that NC 209 drive made me laugh out loud for sheer joy.
Unlikely the leaves will be turning by then though, unless we get an unusually early cold snap.
Nill
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