When the garrison of the Electoral Palatinate marched into Dilsberg Castle, the need for water increased and the well in the castle courtyard had to be deepened. During the construction work the well was ventilated with a shaft which was, however, then filled in at the end of the 17th century when work was completed. Its construction and the original function were forgotten. Soon the saga of an underground passage was told that supposedly led from Dilsberg Castle under the Neckar River to a castle in Neckarsteinach.
The American author Mark Twain was inspired by the saga after a visit to the castle (1878) and included it in the travelogue "A Tramp Abroad" (1880). Twain's story of the castle gallery inspired the German-American Fritz von Briesen to conduct research on the saga. He traveled there from New York and had himself lowered down into the well on ropes, where he ultimately found the entrance to the gallery. With a donation by Briesen it was possible to uncover the gallery again, together with the gallery entrance in the "Höllenberg" forest area, in 1926.