Campground recommendation near Ft. Jackson, SC

There might be something closer to Ft Jackson but we stay at Barnyard RV park in Lexington when visiting our family in the Columbia area. Nothing too fancy but it'll definitely fit your rig.

There is a military campground on Post LINK. It says they accept guests of Service members. Normally this means your son would have to sign you in to the camp ground. However, your son is probably very "occupied" by the Drills right now. Suggest you call the park and ask them how to do it. They go through this every week so they might have a solution.

As above I’d check with the fort. I don’t know of a private RV campground near the fort, Barnyard is not very close, but then neither is much else. I’ve never stayed there. If you have a very liberal definition of “close” then you might try Lake Wateree State park, north of the fort off I77. I know they have some pull thru sites that can easily handle your FW although you’re limited to 30 amp service. There are some commercial parks in the general area.

In Columbia, there is Susquehanna State Park.. It is just off I20, and should be an easy drive to base. I think they may have sites that are large enough. I have stayed there a couple of times in route from South GA to NC. I managed to get sites long enough I didn't have to disconnect my 28 ft TT from my truck for the overnight.

That would be Sesquicentennial State Park, and the reason I did not offer that one up is their website limits the length to 35 ft. The OP might call them and see if they can fit as it would be fairly close to the fort.

We stayed at Columbia/Camden RV Park near Ft. Jackson when running from hurricane Matthew a couple of years ago - no amenities except full hookups but nice people running it.