One of the most visited show caves in Europe is this Slovenian tourist attraction in Postojna that is home to the unique olm salamanders once thought to be baby dragons. Postojna Cave is a karst cave system that runs more than 67,000 feet in length. Archduke Ferdinand I visited the cave in 1819, however, it was first mentioned during the 17th century. The cave has an underground railway so visitors can tour the cave on a train.
See All Things to do in Postojna Cave »