Barbarossa Cave

The Barbarossa Cave is an anhydrite cave in the Kyffhäuser Hills near Rottleben in the east German state of Thuringia. It is a cave with large caverns, grottos and lakes. The anhydrite has formed gypsum on the surface due to the air moisture in the cave and, as a result, has increased in volume. The resulting layers of gypsum gradually separate from the underlying rock and hang like wallpaper from the walls and ceilings of the underground caverns.
It was discovered in 1865 as a gallery was being driven during prospecting work for kupferschiefer, a copper-bearing shale or bituminous marl. By 1866 it had been developed and opened as a show cave under the name of Falkenburg Cave . It has a floor area of about 25,000 m². Of interest to visitors are the underground lakes whose gypsum content gives them an iridescent green colour, and a human made stone construction, known as Barbarossa's Table and Chair .

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