Meet baby dragons in Postojna Cave

Postojna Cave: the delivery room of the human fish

The unusual birth of "dragon" offspring in Postojna Cave

People used to believe that the human fish was the offspring of dragons. And still today we believe that there is something extraordinary, even mythical, in them. The human fish is one of the most impressive dwellers of the karst underground. Postojna Cave can also boast a unique attraction. On 30 May 2016, the first offspring hatched from one of the eggs of the human fish. This was a remarkable historical event that captured the attention of the entire global public. The first hatchling was followed by 21 little dragons that became world stars immediately after being hatched.

The lively little human fish from the first clutch are being joined by a new generation of baby dragons in 2022. From a total of 43 eggs laid by a female olm at the beginning of June, we are eagerly awaiting 32 hatchlings. The team of the cave laboratory thus succeeded in attaining a record 74-per cent reproductive performance.

Follow the 2022 Olm Diary

What makes the baby dragons such stars?

You may be wondering why human fish are so special. Although they have lived in caves for millions of years, humans first observed them only 400 years ago. Believing that there was a fearsome dragon living inside Postojna Cave, people thought these animals were in fact baby dragons!

Today, we know that the human fish, also known as the proteus, is the only vertebrate living exclusively underground. This small animal is extremely well adapted to life in the darkness. Its skin lacks any protective pigmentation, so it is pale pink in colour and resembles the skin of people, which is why it was given the name “human fish”.

The human fish only reproduces every six or seven years. Of over 100 eggs deposited by a female olm in its lifetime in its natural environment, only two offspring would reach maturity. This is why the survival of 22 hatchlings from a total of 64 eggs laid in 2016 and 32 hatchlings from a total of 43 eggs laid in 2022 in the Postojna Cave laboratory is really an incredible achievement.

Preserve the olm

The underground world of Postojna Cave is the kingdom of the olm. In order to keep the environment as clean as possible and to ensure the existence of olms, the Protect Proteus project has been established in Postojna Cave. The project provides an optimal environment for the dragon babies, works with international experts, ensures a cleaner underground and raises awareness about the importance of a sustainable way of life.

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Discover the most interesting facts about the human fish that are perhaps as yet unknown to you.

The human fish is definitely a unique phenomenon, as the following facts attest.

The olm or human fish is the largest cave predator, although it grows to only 30 to 40 cm in length.

It is resistant to long-term starvation and can live up to 12 years without food.

The human fish could offer us advice on living a long life, as it lives up to 100 years!

Its presence is an indicator of clean water, since it only lives in extremely clean (underground) water.

Baby dragons’ "roommates"

Postojna Cave is considered one of the most beautiful and most biologically diverse karst caves in the world. In addition to the human fish, the cave is also home to more than 150 other animal species. Meet some of the most interesting ones in the vivarium!

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Explore the magnificent habitat of the human fish

Postojna Cave is the longest cave in Europe open to visitors. The River Pivka created a magical world of tunnels, underground halls and dripstone galleries, and these have been attracting visitors for over 200 years. Take a ride on a train along the oldest cave railway in the world into the depths of Postojna Cave.

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A holiday in true James Bond style

Mysterious passages, behind-the-scenes intrigue, luxurious spaces and a romantic atmosphere—all of these would surely pique the interest of the famous secret agent 007. Treat yourself to a holiday at the Hotel Jama and explore the mysterious world of the Postojna Cave Park. Here are 007 reasons to embark on a Bond-themed adventure.

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The karst world is amazing!

Rather than just exploring the phenomena of the karst caves, learn also about the special features of the surface of the Karst – the area that gave its name to all the karst phenomena around the world. You can find them in nature, cultural heritage and cuisine.

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Postojna cave

Postojna Cave and Predjama Castle are world-class attractions!

Karst

The world of underground wonders, stunning natural phenomena and unique tastes.

Mediterranean & Karst Slovenia

Global surprises from salt pans to karst caves.

EXPO Postojna Cave Karst – travel through time and space

Explore the creation of karst caves and other karst phenomena and the development of life in them.

Caves

Stunning underground caves, including the world-renowned Postojna Cave.

Lipica

Lipica is a renowned cradle of the Lipizzaner horse breed in Europe.

Spend the day at one of the most unusual Slovenian museums

Experience history in a fun and interactive way.

Follow ivy branches to find your way to osmice wine bars

If you visit the Primorska wine region, be sure to visit the typical osmice wine bars, occasional wine bars, where you will be served local wines and dishes.

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Meet baby dragons in Postojna Cave