We make the most of Budapest as a city, with stunning architecture and diverse culture for all mindsets and lifestyles. But you may be surprised to learn that there is also a lot going on beneath the city’s bedrock. We’re not talking about another new metro line or an invasion of gophers, but rather the extraordinary system of underwater caves that supply the city’s dozen or so thermal baths with warm water. This may be one of Budapest’s best kept secrets, though it won’t be for long, as the Hungarian Tourist Board teamed up with media company Great Big Story to make a video about the largest and most explored underwater cave beneath Budapest: János Molnár.

Before diving into the video, here are a few interesting facts about the János Molnár underwater caves:

The opening to the network of caves was discovered in the 1950s by none other than a man named János Molnár, a pharmacist who decided to follow the warm waters of a thermal bath to their source. Divers began charting the caves in the 1970s, and since then four miles of underwater caves have been explored.

The largest underwater chamber of the network can fit (according to the video) 350 double-decker buses. Were it a bath, it would take four-and-a-half years to drain.

This is only one complex of underwater caves in Budapest. Many still exist that have yet to be explored.

Entirely new species of underwater life have been discovered in the János Molnár caves. Biologists, geologists, and chemists visit to study the water's unique properties.

Moreover, you can visit too, as dives are arraigned through a private company. As described by somebody who experienced the caves under Budapest first hand to travel site Atlas Obscura, “Inside, the network of water-carved tunnels curve into bends with striking, pinkish mineral formations decorating the walls. Some of the shapes lie in undulating layers, others resemble small cauliflower heads, while some of the mineral deposits mimic flowers, which earned the cave its nickname the ‘Underground Flower Garden.’”

But if you aren’t certified/in Budapest/ or are claustrophobic, have a look at this spectacular video, which has racked up almost 100,000 views in the few days since it was uploaded, and get to know Budapest’s thriving ‘underground’ culture.

All photos by Janne Suhonen are used by permission. You can find out more about Janne's book and photo projects here and here.

Flatpack Films is based in Budapest, Hungary. We are a film company that offers an inspiring and professional work atmosphere for our local and international clients. Since our inception, our focus has been providing the best of the best in terms of local production resources, locations, cast, and technical teams to ensure that whatever the production we facilitate, we do to highest standard possible.