Devils Marbles (Karlu Karlu)

The Devils Marbles, known to the local Warumungu people as Karlu Karlu, are a field of large granite boulders roughly 105 kilometers south of Tennant Creek in the Northern Territory of Australia, forming the exposed top of a much larger buried granite mass. The granite hardened from magma far underground, and later uplift and pressure release let it expand and crack into blocks; long cycles of daytime heating and nighttime cooling then split many of the blocks cleanly in two, while others remain precariously balanced one atop another. The site is now protected as the Karlu Karlu / Devils Marbles Conservation Reserve.