Neptune’s Grotto is a stalactite sea cave carved at the foot of the 110-metre-high Capo Caccia cliffs on the island…
Salina Slănic
Slănic mine is an old salt mine, located in Slănic, Prahova County, Romania, just 100 km north of Bucharest.
Postojnska jama
Postojna Cave is a 24,120 m long karst cave system near Postojna, southwestern Slovenia. The caves were carved by the Pivka River.