The Postojna Cave is one of the largest cave systems in the world, with over 24 kilometres of underground tunnels, galleries, and chambers.
The cave system has been open to the public since the early 19th century, and visitors can explore the caves on a guided tour.
The tour takes visitors through a series of spectacular chambers filled with stalactites, stalagmites, and other breathtaking geological features. One of the highlights of the tour is the Concert Hall, a massive chamber where concerts are held due to its impressive acoustics.
The Postojna Cave also has a unique attraction - the proteus, a rare amphibian that can only be found in underground caves.