This is a mine debris pile they are very common as they reside in front of most of the mines in Nevada. Debris was often collected then thrown down the hillside. These are very dangerous to slide down I almost broke my arm and injured myself in 2008 on one. However if you side step it right you can venture up and down them. Sometimes it is the only way to exit or enter a mine. In this case the mine debris pile sits behind the ghost town of Berlin and with everything we do we prefer the more adventurous route.