Orlova Chuka
The 14th longest cave in the world
13.4km · Length
Orlova Chuka is a cave situated in the Danubian Plain, north-eastern Bulgaria. With a total length of 13,437 m, Orlova Chuka is the second longest cave in the country after Duhlata. The cave was discovered in 1941 and opened for tourists in 1957. Orlova Chuka is home to 14 species of bats.
Cave data from Wikidata (CC0). Summary from Wikipedia (CC BY-SA).