Chris: I don't know if you already made your plans, but we just stayed at Greenbelt Campground in DC last week for 4 days. We found it to be a very nice, heavily wooded park with lots of wildlife and good safe asphalt roads for the kids to bike and scooter. There were hot showers and flush toilets and utility sinks for washing dishes. The park was not very crowded at all when we were there and most days we had a lot of privacy. The campground is 2 miles into the 1100 acre park, but the interstate entrance is just a block or two from the gate to the park. The prices can't be beat (only$8 with Golden Age Pass, and regular $16). Because of the wooded sites, it seemed 10 degrees cooler than in town and there was a breeze so we didn't need any AC, even though it was in the 90's. There is a ranger station at the entrance, and the park was patroled regularly. The village of Greenbelt is just a few blocks away and has free internet at the library and the town itself is worth a visit for the interesting history. It was an FDR WPA planned development community, one of 3 in the U.S. during the early 1930's, so it has an art deco theme. As mentioned, the downside is no electric hookups. We used our battery
power conservatively for the 4 days we were there, and had a very enjoyable stay.