13. Eisriesenwelt – Austria
In German language, Eisriesenwelt means “The World of Ice Giants”. This cave, which is worthy of the name and looks like from another planet, is located in Northern part of Austria. It is the largest ice cave of the world. It is 400 meter below the ground level and its end-to-end length is 42 kilometers. Visitors are allowed to see the part of the cave that is seen in the picture. Once upon a time, in the old ages, this part is thought to be a glacial door to hell. It is possible to see the place with guided tour programs from May to October.