Interesting facts

In 1831 the first true cave beetle known to science, the slender-necked Leptodirus, was found here, overturning the belief that caves held no life.

More than 175 animal species are recorded from the Postojna–Planina cave system, including about 115 true cave dwellers, often described as a world record.

In April 1944 Slovene Partisans crept in through a half-blocked passage missing from German maps and blew up a fuel depot; the fire raged for a week.

Soot from that wartime blaze still blackens part of the cave, and many formations broke off the ceiling in the heat.

Signatures scratched on the walls go back to the 13th century, centuries before organised tourism began.

The first visitor carts on the cave railway of 1872 were pushed by the guides themselves; a gas locomotive took over only in the early 20th century.

During the First World War, Russian prisoners of war were made to build a bridge across a deep chasm inside the cave.

The Concert Hall chamber covers about 3,000 square metres, holds up to 10,000 people and has hosted symphony orchestras.

An underground post office opened inside the cave in 1899 and is described as the first of its kind in the world.

The cave was carved by the Pivka River, which sinks beneath Sovič hill and reappears beyond Planina Cave as the Unica; more than 24 km of passages are explored.

Why it is worth it

Long before anyone lit a torch in Postojna's deeper chambers, the cave already had a reputation. In 1689 the Slovenian polymath Johann Weikhard von Valvasor recorded local accounts of pale, snake-like creatures that occasionally surfaced in floodwater near the entrance — animals with four small legs, a long tail, and skin the colour of a corpse. People took them for baby dragons. They were, in fact, a blind aquatic salamander now known as the olm (Proteus anguinus), a species that lives its entire life in permanent darkness, can go without food for years by slowing its metabolism almost to a stop, and is thought to live for a century or more. It took until 1768 for the animal to get a scientific name, and years longer to confirm it actually lived in the cave rather than washing in from somewhere else.

The cave people could already walk into — the outer galleries — had been visited since at least the Middle Ages, but the far more dramatic inner system stayed hidden until 1818, when a local candle-lighter named Luka Čeč, preparing the cave for a visit by the Austrian emperor, pushed past a narrow passage and found himself in a much larger network of halls. Postojna moved fast after that: a Cave Tourist Board was already organizing visits within a year, and by 1884 the passages had electric lighting — installed before most street lighting in Vienna. In 1872 an underground railway was added for visitors, one of the earliest uses of rail transport built purely for tourism rather than mining or industry.

The olm never stopped being the cave's quiet headline act. It's notoriously difficult to breed in captivity because it reaches sexual maturity so slowly, so when one of Postojna's resident olms laid eggs in 2016 and they hatched under observation, it drew scientific attention from well beyond Slovenia — a rare, documented look at the reproduction of an animal that had spent three centuries being mistaken for a myth.

Good to know

The cave sits at a near-constant temperature of around 10°C year-round regardless of the season outside, and access to the inner galleries is only by guided tour.

Getting there

38 km from Ljubljana. Ljubljana Jože Pučnik Airport (LJU) is about 53 km away.

Hours	—
Price	33.50 EURper OpenStreetMap
Season	—

Stroller	—
Wheelchair	yesper OpenStreetMap
Dog	—
In the rain	—

Postojna Cave

Interesting facts

Why it is worth it

Good to know

Getting there

Plan your visit

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