The Devil’s Corkscrews

(via Amusing Planet) In the mid-1800s, ranchers across Sioux County, in the US state of Nebraska, began unearthing strange, spiral structures of hardened rock-like material sticking vertically out of the ground. The spirals were as thick as an arm and some of them were taller than a man. Not knowing what they were, the ranchers began calling them “devil’s corkscrew.”