Though it looks like any old natural geological structure standing high above the ground, much like the rock formations in the Grand Canyon or other places, it is actually a 3,400-year-old ziggurat built during the time of King Kurigalzu of the Kassite Dynasty.
The structure was originally a ziggurat standing some 60 meters tall with a foundation about 70 meters square. What remains today is the core; the rest was destroyed along with the city of Dur-Kurigalzu that was invaded by the Elamites in the 12th century BC.
(Image credit: Wikimedia Commons)