Danube Sinkhole Danube Sinkhole The Danube Sinkhole ( or ) is an incipient underground stream capture in the Upper Danube Nature Park. Between Immendingen and Möhringen and also near Fridingen (Tuttlingen), the water of the Danube sinks into the riverbed in various places. The main sinkhole is next to a field named "Brühl" between Immendingen and Möhringen. The term “sinking” is more accurate than “seeping”, because, instead of just distributing into the soil, the Danube’s water flows through underground caverns to the Aachtopf, where it emerges as the river Radolfzeller Aach. The sinking Danube water disappears into a karst water system of
Cave Without a Name human contact with the cave began only in the early 20th century, when a small farm animal became trapped in the small external opening of the cave, known as a sinkhole. The cave went largely unnoticed again until the 1920s during the era of Prohibition when a small moonshine distillery was installed in the uppermost cavern. It again fell into obscurity until three local farm children rediscovered the sinkhole in 1935. These children are believed to be the first who actually entered the main chambers of the cave. After the rediscovery, Jim Horn, the original owner of the property decided