 In the 1920s, the caves were used as a restaurant and nightclub venue known as the Wabasha Street Speakeasy.The speakeasy was said to have been frequented by gangsters such as John Dillinger and Ma Barker, however there is no evidence that these visits occurred; thus, these stories are considered legend.On October 26, 1933, Josie & William Lehmann opened the Castle Royal, which was built into the side of the caves.