This is a beautiful 18,000 acre park operated by the National Park Service. The web site indicates RV's are restricted to 32 ft, but this is not true. Larger units can be accommodated. All sites are heavily wooded and the campground is 7 miles from the entrance to the park. The staff and campground host are very helpful and friendly. This is a campground for people who want to be close to nature. If you desire swimming pools, etc., this park is not for you. It is within a 1/2 mile of I-95 located just 30 miles south of Washington D.C. We camped here in a Motorhome.