Postojna Cave

Postojna, Inner Carniola, Slovenia

---

Postojna Cave, located near the town of Postojna in Slovenia’s Inner Carniola region, is one of the most famous karst cave systems in the world and the country’s most visited natural attraction.

Formed over millions of years by the action of underground rivers on limestone, the cave system extends for more than 24 kilometers and features spectacular halls, tunnels, galleries, and rock formations. The cave is renowned for its stunning stalactites, stalagmites, and vast underground chambers. Visitors explore part of the system on a unique electric train ride followed by a guided walking tour.

It is also home to the rare olm, a blind amphibian often called the “human fish,” which is found only in the underground waters of the Dinaric Karst region. With its extraordinary geological features, rich biodiversity, and fascinating underground landscapes, Postojna Cave is one of Europe’s most remarkable natural wonders and a highlight of any visit to Slovenia.