This is one attraction that you should not miss when you visit Mt.Rushmore. Everything here defies the laws of nature that we know of. Balls roll upward, water flows upward and you can’t stand straight. The tour of this area is a guided tour and they explain you about the history and the phenomenon very well. It was very exciting to be at this place. The tour runs for about half hour and we enjoyed the half hour well. I definitely recommend this place.