Alba Regia Cave is one of Hungary's most remarkable underground systems - the longest and deepest cave in the Bakony Mountains, and the fourth deepest cave in the entire country. For many years it was even considered the nation's third deepest cave. This is a destination for serious cave explorers rather than casual sightseers.

Formed in Lower Jurassic and Upper Triassic Dachstein limestone, the cave's passages form stepped levels with height differences of 10-20 metres, shaped by the dip of the rock layers. Inside, visitors (with proper permits) can find varied dripstone formations including draperies, stalagmites, stalactites, straw stalactites and rare teratoma formations. The atmosphere is wild and demanding — in the deepest sections, carbon dioxide concentration reaches around 4%, occasionally measured as high as 5.5%, making exploration genuinely challenging.

How to get there

• Csőszpuszta (near Isztimér) — approximately 2 km on foot to the northeast, on the Tés Plateau, on the eastern slope of Köves-domb; requires caving experience and orientation skills

Practical information

• The cave is under strict protection and sealed with a concrete ring and iron grate
• Entry requires a permit from the Duna-Ipoly National Park Directorate and accompaniment by a caving group
• Basic caving equipment and experience are mandatory
• Visits are prohibited during the bats' resting period
• The cave is one of the region's most significant autumn mating sites for bats, particularly the lesser horseshoe bat

Detailed faunistic surveys have identified 216 animal species within the cave, and the edible dormouse is regularly found here — even at depths of 130 metres in carbon dioxide-rich sections.