Guess what: they’re all in Europe (unless you want to argue about the location of Georgia). Some of them run a mile or more deep into the earth, although to actually go a mile deep, you’d have to trek or rappel for miles and miles. The world’s deepest cave for now is 7188 feet (2191 m) deep, although with research, that record can always be broken by those who feel the need to explore the “bottomless pits” of the world. Link -via Geek Like Me
(image credit: Plamen Stoev)