Slovenia is known for being one of the most ... The stunning Predjama Castle, the largest cave castle in the world, is built ...

Eking through them on an illuminating guided tour is one of Slovenia’s great travel experiences and much more rugged and rewarding than the touristy Postojna Caves, with their tourist train.

Why Do a Day Trip to Postojna Cave and Predjama Castle? Postojna Cave – Slovenia’s Most Famous Cave – Ride a unique underground train through vast caverns filled with stunning stalactites ...

"After a week of preparations above and underground, the ‘cavenauts’ are set to explore a cave in Slovenia where they will live and work for six days," the ESA website says. Course designer ...