Črna jama is a karst cave and one of the entrances to the vast underground system of Postojna Cave and the underground Pivka River. It takes its name from the large dark cave formations found inside, and it offers a fascinating glimpse into Slovenia's hidden underworld.

The cave lies in the middle of a forested karst plateau, its entrance opening at the bottom of a large collapse doline. Inside await spacious chambers and horizontal passages with striking dark formations that give the cave its name. A large part of the 3294-metre-long cave was already known in the Middle Ages, when visitors from Postojna were guided through it, and it was even visited by the famous polymath Valvasor.

How to get there

• Postojna — by road via Veliki Otok, approx. 3 km northwest of Postojna, accessible by car

Practical information

• The cave is lit and arranged for tourist visits, accessible only with a guide

During World War II, a group of partisans passed through Črna jama and a connecting tunnel to set fire to a German fuel depot in the entrance section of Postojna Cave, escaping safely back to the surface through the same entrance. The cave also gained fame through the Slovenian film Ne joči, Peter, in which its discovery is attributed to a young boy named Peter.