Hill City Rushmore KOA is expensive but if you have kids...or grandkids with you it’s a destination itself. Was there couple weeks ago. Just left Grizzley in West Yellowstone. Very nice, expensive and very convenient to the park. Told us they start accepting reservations in Oct for the next season and get a thousand calls the first day. Made our res last December. Talked to a guy who reserved in Jan and had to change sites every day.