We arrived on a Monday afternoon without reservations, and there were many sites to choose from.  The Campground Hosts helped us to complete our reservation (no cell signal here).  Very clean and well maintained campground.  There were nightly Ranger Talks at the Amphitheater.  Campground is very close to the Wind Cave Visitor Center and the tours there.  We took a half-day trip to do a tour at Jewel Cave.  Restocked supplies in Hot Springs.