10 of the World’s Most Breathtaking Caves (6 of 6)

10. Vatnajokull Glacier Cave, Iceland

Situated in the largest glacier in Europe, the Vatnajokull in Iceland, this cave — like many others of the sort — was formed as a result of melting glacial ice water. But use caution if you do visit — glaciers are prone to breaking, and what you don’t need is several tons of ice landing on you.