We went last year to Tennessee from NE Ohio also, we took I-71 and picked up I-75, went through Cincinnati and Ky, and it was a pretty easy drive. The mountain passes weren't as big as I-77 through WV area. We went to the same gatlinberg area as you. Once you get south in KY and into TN you'll have some longer hills and grades but nothing that would be concerning. Either way, take your time and stay to the right . Enjoy it there, it's a bueatiful place.
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