Molnár János Cave

Molnár János Cave is an underground thermal system beneath Budapest with passages running through limestone formations. The cave system spans several kilometers and is fed by natural springs with warm water that creates visible mineral deposits throughout its passages.

A pharmacist named János Molnár explored the dry sections above Lake Malom in the 19th century, revealing an extensive underground network beneath the city. His investigations established scientific interest in the site and opened it to further research and exploration.

The cave is named after the pharmacist who first studied it, connecting local history with scientific discovery in a way visitors can trace today. The thermal waters that flow through it have long fascinated researchers and remain central to how people understand this underground world.

The entrance is located near Lake Malom with accessible sections available for visitors to explore. Guided tours are the best way to move through the passages safely and learn about how the thermal system works.

Water temperatures stay constant between 20 and 25 degrees Celsius throughout the year, supporting special mineral formations and rare organisms. This stable underground environment allows unique biological processes that researchers continue to study and document.

Location: Budapest

Part of: caves of the Buda thermal karst system

GPS coordinates: 47.51788,19.03589

Latest update: December 8, 2025 21:00