This is where the Empire State Building was born - or at least where the materials came from. 18,360 tons of limestone came from this quarry to build the iconic New York behemoth - and, in fact, the finest limestone in the world comes from the quarries of Indiana. The Empire Quarry is the most famous and perhaps one of the longest and the deepest. Diving off the cliffs is ill-advised though. Many a daredevil has sustained an injuring from doing just that.