Slovenia - Everything you need to know about Postojna cave

Carved over thousands of years by the Pivka River, the Postojna Cave is a vast subterranean network of passages, galleries and chambers which have attracted visitors for more than 200 years. On your Slovenia holiday, a visit is a must.

Stalagmites and stalactites

Inside you’ll discover a wealth of stalagmites and stalactites, made when slowly trickling water leaves deposits of calcium carbonate and other minerals. These jagged, dramatic-looking forms, which hang from the ceiling and sprout from the ground, can sometimes grow together to form huge pillars of rock.

One of the most notable stalagmites in Postojna is called ‘Brilliant’, and when you see this snow-white column of rock rising five metres from the ground, you’ll see just how it earned its name.

Underground adventure

Your journey into this underground world is via an electric train, whose tracks were laid in 1872. Over 90 minutes you’ll be taken on an incredible 5km journey to the centre of the earth, where you’ll also have the chance to explore on foot with an expert guide. You’ll see formations that have taken thousands of years to morph into remarkable shapes – it takes decades for just one millimetre to form and centuries to grow a centimetre. 

Predjama Castle

Close to the cave is Predjama Castle, which is built within the mouth of a cave and has perched on a rocky cliff for more than 700 years. Take a look inside, where renovated rooms, a chapel and a dungeon give you a fascinating glimpse into the past.