The List Universe are listing 10 of the most interesting / deepest / difficult to pronounce "Holes" in the Earth including Chuquicamata, Udachnaya Pipe and good old (now deserted) Kimberley Diamond Mine, South Africa. I once flew over the Kimberley mine on a day flight between Cape Town and Jo'burg. Fascinating to see such a man-made wonder.

This one is called the Great Blue Hole in Belize. See all the other spectacular holes here.