Subterranean adventures

The exploration of the mysterious underworld, where the light of day never shines, is a special adventure on its own. You can explore the underground on foot, with kayaks or cycle from one valley to another by bike.

The ore deposits between Mount Peca and Uršlja Gora were discovered already by Romans. In the years of active mining, more than a thousand kilometres of tunnels were dug out, where you can still hear stories of the miners’ life and be amazed by nature’s wonders. The Peca Underground – Tourist Mine and Museum is one of the central tourist attractions of the cross-border UNESCO Karavanke Geopark with its selection of unique subterranean adventures and experiences. You can take a train to the heart of the mountain and continue on foot to explore the underworld. If you are looking for a more adrenaline-packed visit, you can explore the underground by cycling or rowing a kayak to the flooded parts of the tunnels. An even longer tradition of tourist exploration of the Koroška underground is held in the Huda Luknja cave, which is a real subterranean marvel of the isolated karst. Here you can experience a true adrenaline-packed trekking adventure with the help of a guide.

Black hole trail





Podzemlje Pece (Peca Underground) – Tourist Mine and Museum Glančnik 8, 2392 Mežica

Experience the crazy cycling adventure in the Peca underground, suitable only for technically skilled and experienced mountain bikers.

The extreme adrenaline mountain bike adventure in the underground of a former mine is a challenge even for the technically most skilled and experienced.

Black Hole Trail is a special challenge even for the most skilled mountain bikers. The trail runs through abandoned tunnels of the Mežica mine. From the day it closed down to the day they started setting up the trail, no human foot stepped into these tunnels. The vast halls were once filled with tons and tons of lead ore.

The extreme adrenaline mountain bike trail represents an unforgettable adventure even for the most skilled and experienced mountain bikers. The trail is filled with challenges and technically demanding sections. The trail descends over five horizons for about 150 metres in altitude. Every now and then you will encounter very interesting sections, where you can relax for a moment and soak in the endless blackness of the great halls. Of course, if any section is too difficult, you can always conquer it on foot.


The Black Hole Trail has been awarded the Slovenia Unique Experiences – Recommended by Slovenian Tourist Board label since 2023. It is a unique experience included in a carefully selected collection of experiences marketed under the Slovenia Unique Experiences quality brand and supporting the story of green boutique Slovenia and the I feel Slovenia brand.

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