Karlu Karlu – The Devil’s Marbles

(via Amusing Planet)  Devil’s Marbles or Karlu Karlu, as they are known by the local Warumungu Aboriginals, are a collection of massive granite boulders strewn across a shallow valley, 100 kilometers south of Tennant Creek in the Northern Territory, Australia. Formed by erosion over millions of years, the Devil’s Marbles are made of granite with sizes varying from 50 centimeters up to six meters across. Although they appear to have been carefully placed or perhaps brought by flood, the boulders actually formed on the ground they stand by erosion of rock that reached the surface from below.