Usually when we head down we deadhead until either Savannah or Charleston and spend a couple days, then continue on to Bradenton. Nothing on I95 in between Maryland and those cities really captivates me.
I would suggest you consider either of those 2 cities while you are down there. I haven't found a campground in Savannah that I LOVE... but we spend little time at the campground when we are there. For Charleston, James Island County Park (JICP) is a GREAT home base. Nice sized sites with a wooded setting, fair price, close to the city and food.
Another option is to go down through the western side of the Carolina's through the Blueridge Mountains and through those areas. I've never driven that route, as we are usually strapped for vacation time and I95 is the quickest route. I can't recommend any specific campgrounds there though.
Sounds like a heck of a trip! Hope you have a fun and safe drive and winter!
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