The Postojna Cave—a subterranean wonderland of karst tunnels, caverns, and galleries, adorned with dramatic stalagmites and stalactites—is one of Slovenia’s most remarkable natural wonders and among the country’s most visited tourist attractions. It stretches along the Pivka River for an impressive 12.5 miles (20 kilometers).

You will explore part of the picturesque underground world of Postojna Cave during a train ride on the world's only double-track cave railway. Make sure you are sitting comfortably and enjoy the unforgettable scenery.

Postojna Cave is the cradle of speleobiology as it is inhabited by over 150 species of cave-dwelling animals. Since they are almost impossible to see during a cave visit, you can meet them in the Vivarium – an underground zoo.

Perched in the middle of a magnificent rocky cliff, a mere few kilometres from Postojna Cave, is the picturesque Predjama Castle, the inspiration for many a story and legend for the past 800 years.