We take 77 to 26 in South Carolina (I think) then head over to 95 straight down into Florida. We live maybe 15 minutes from 77, and it would take us hours to drive over to 75.
Randmcnally sometimes does not have the "best" directions. I would definately check with AAA if you are a member (like WDWisTheBest suggested).
Coming from the east side of Columbus, the I-77 route makes more sense to us. As long as the weather looks good, 77 will be the way. If the mountains of WV/VA/NC look bad, then we may switch to a I-75 route.
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