Paula - I found this campground surfing the Net. They were the only campground within miles of Washington D.C. I cabin camped there in September 2003.
Campground Review
Aside from the great location, the campground itself is extremely well maintained and well managed. They can accommodate hundreds of RVs, and they also have several very nice tent campsites. The cabins are reasonably priced at $55 per night, and they have kitchenettes and sleep up to four. They have very nice shower houses located throughout the campground, as well as two playground areas for the kids. They have a convenience store at the main gate where there is a bus stop that will take you right in to D.C. They also have a community center, game room, laundry room, grill, and two pools. They offer a tractor ride around the campgrounds every evening. It's a very warm and wonderful place to stay.