Beneath the old town of Kranj, there are 1,300 meters of underground tunnels built during World War II, which in the past served as a city shelter. Today, this secret underground network hosts much more pleasant social events and activities.

The tunnels have become home to rare cave animals, such as cave locusts and cave spiders. Among the interesting, but very rare inhabitants are also nocturnal bats, whose extraordinary flying skills surpass acrobatic flyers and even manage to catch dinner in the process.

Over time, the underground tunnels have acquired a natural patina, which includes real stalactites, and in the cold winter months, ice stalactites. They are created in conglomerate soil, and in parts where they are not surrounded by concrete, their natural structure is clearly visible.

Visitors can admire various temporary exhibitions in the tunnels, including mineral and fossil exhibitions, as well as a reconstruction of a World War II air raid shelter. This interactive experience allows visitors to experience a simulated air raid, adding an additional dimension to this unique attraction. The Kranj Underground Tunnel thus combines history, nature and culture, offering visitors an unforgettable experience.