The caves are unique on a European scale and feature carbon dioxide “lakes.” These were created in part by underground thermal water. Remarkable formations are composed of the mineral aragonite, and the site also features raft stalagmites and walls with spherical incrustations known as doughnuts.

I.: Closed
II.–III.
Mo–Fr 10.00 am, 2.00 pm
IV.–VI., IX.–X.
Tu–Su 9.00 am – 4.00 pm
VII.–VIII.
Tu–Su 9.00 am – 5.00 pm
XI., XII.
Mo–Fr by arrangement