Portoroz

No matter how short on time you are, do not miss out on visiting this magical creation by nature. Postojna Cave, situated near Postojna, is the largest cave system in Slovenia. It is the longest open public depth of any cave in the world which attracts more tourists than any other attraction in the country. This Karst Cave system, created by Pivka River, was first discovered in 17th century and made open to general public in 1819. It is also home olm, the largest trogloditic amphibian in the world. Cave trekking for a group of 3-15 people is organized here.