One of the best experiences on our Slovenia vacation was visiting the Postojna cave.

The formation of Postojna Cave goes back to approximately three million years ago when it started to be formed in 70-million-year-old limestones.

There are 24km of underground passages, galleries, and halls in Postojna cave.

After a 3.7 km long train trip through the underground we started a guided 1.5 km easy walking tour through the cave.

The cave tours last around an hour and a half. There are tour guides taking through each group of visitors.

There are Slovenian and English tours available but there are also audio guides available for many other languages. 😊

Temperature in the cave is constant throughout the year at around 10 degrees Celsius so warm clothes are recommended for the tour.

I was at the caves last when I was in elementary school. Although I knew what to expect I was again impressed with the nature’s wonderful creations.

The cave was first described in the 17th century by the pioneer of study of karst phenomena, Johann Weikhard von Valvasor, although graffiti inside dated to 1213 indicates a much longer history of use. In 1818, when the cave was being prepared for a visit by Francis I, the first Emperor of the Austria-Hungary, a new area of the cave was discovered accidentally by Luka Čeč, a local man in charge of lighting lamps in the cave.
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In 1872, cave rails were laid along with first cave train for tourists. At first, these were pushed along by the guides themselves, later at the beginning of the 20th century a gas locomotive was introduced.

It’s crazy to think our tour guides would be pushing us along in the rail cars and that anyone would want to have that job in the first place 🚂

Below you can see the so called Russian Bridge. During World War I, Russian prisoners of war were forced to construct a bridge across a large chasm inside the cave.

Postojna Cave was carved by the Pivka River over millions of years. There are stalagmites, stalactites, and formations called curtains or draperies that look like folded curtains.

The oldest dated stalagmite located along Postojna Cave's tour route is called the Skyscraper, and its sheer grandness speaks volumes about its age – it is 16 metres in height and so wide that, seen with the naked eye, it does not look like a dripstone, but rather like a striking flowstone wall located beside the tour path. Scientists used a special technique to date it and its official age is not "so old it's impossible to pass", but has been estimated at about 150,000 years.

The formations are in different colours. The ones that are more orange contain iron oxides. The most adored one is supposedly the Brilliant which is made of limestone only. It’s also the symbol of the Postojna cave.

Looks pretty stunning, don’t you think? 🤩

I hope you liked seeing another natural gem from Slovenia 🇸🇮