Even though I currently live in Ohio I'm very familiar with that area. I own property at Elloree (about 6 miles away from Santee). The DW and I like Santee State Park, but it's really not much. It's about 5 miles from Santee, all the roads and campsites are dirt and that's about it. For 1 night, passing through, I would suggest Santee Lakes Campground. It's right off of I 95 (Exit 102) It's a Good Sam park. It's right across the lake from Santee. They have their own web site that you can check out. I've never stayed there, but I think it's your best option. Let me know if you have more questions.
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