The Sailing Stones of Death Valley

image credit: James Gordon cc
Death Valley, located in Eastern California, USA, hosts one of the most enigmatic geological phenomenon that has puzzled scientists for decades. In Racetrack Playa are the 'sailing stones,' which seem to glide across the flat dry desert on their own, without human or animal intervention.
Although no one has actually seen the stones in action, their movement is evident in the long tracks on the ground they left through the years.