Fantastic Caverns in Springfield, Missouri, is a show cave famous for North America’s only completely ride-through cave tour, with visitors traveling by Jeep-drawn tram along the path of an ancient underground river. Discovered in 1862 by John Knox and his hunting dog, it remained secret during the Civil War so neither Union nor Confederate forces could use it for saltpeter. After its first exploration in 1867, the cave developed an unusual public history: it was later used by the Ku Klux Klan, served as a speakeasy during Prohibition, hosted concerts in the 1950s and 1960s, became a fallout shelter in 1970, and endures as a major local attraction.