When I was last there #5 was best for trailer camping. They might have opened full hook up sites by the rest rooms. There were three full hook up sites when I was last there. Not all sites are accessible with a trailer. Call the rangers there and ask what sites are available for trailer camping. I liked 5 because it has a great view of the mountains and lots of game to view. The place is awesome. If you go ask for a tour to the Indian caves, the cave art is unbelievable.