Gasp at amazing geological formations within the Postojna Cave. The show cave is the largest in the “classic karst” and among the most visited in Europe. Your tour begins with a cave train ride on railway lines that were laid in the 1800s. Wind your way through dark mazes and vast open chambers, like the Gothic Hall, in temperatures ranging from 8 and 10 degrees Celsius, and learn the unusual way the Postojna Cave’s geological past was recorded. A wealth of geological formations of various shapes, colors, and age have formed the cave’s halls including those from calcite, stalactite, and stalagmites. You’ll have the chance to depart the train at the Great Mountain so you can walk deep into chambers to view these amazing formations. The Pivka River has carved the cave for at least two million years creating multi levels and limestone layers. People have frequented the cave as early as the 13th century, but it wasn’t until the 1800s that it became open to tourists. Germans, during World War II, used the cave to stash large supplies of gasoline, but the Partisan army destroyed the collection. As many as 100 animals have dwelled in the cave. You will see some of them in the caves’ modern aquarium as well as collections of ancient remains from the Ice Age creatures that were discovered.