Externsteine

The Externsteine are a distinctive group of tall, narrow sandstone pillars rising up to about 40 meters from the Teutoburg Forest near Horn-Bad Meinberg in North Rhine-Westphalia, Germany, formed from a resistant band of Cretaceous-age sandstone that was tilted nearly vertical by tectonic compression during the uplift of the surrounding hills. As softer surrounding rock eroded away over millions of years, the harder, steeply tilted sandstone bed was left standing as a row of separate rock towers divided by narrow gaps, a formation process similar in principle to other tilted sedimentary ridges though unusually pillar-like in its individual towers. The rocks have long been culturally significant, bearing medieval rock-cut chambers, carved reliefs and staircases, and remain a subject of continuing debate over their pre-Christian and early medieval use.