2nd week of September, 2017. Desert camping. CG was crowded and no real privacy. Restroom are clean, no showers. No hookups. Water available, but boil order in effect while we were there. Be sure to fill tank before arriving. Very bad washboard road into park. 10-15 mph. Why come here? The Great Houses are amazing! Good hiking. We loved it!
Campground was full so I did not stay there. However a ranger at the visitors center said I could park overnight in either the visitors center lot or a nearby lot outside the loop road gates. My unit is a self-contained Roadtrek van so that was no problem and it was free. I was alone all night. Another plus is that the park has gold-level night sky status and I was able to enjoy that sky without light from others.