Tianmen Mountain, China
Jeb Corliss is nuts, crazy, a couple burgers short of a Happy Meal. There's no other way to describe it. Corliss, the BASE jumping guru, has plied his extreme sport on nearly every continent. He's jumped from the Eiffel Tower, tried his best to soar from the Empire State Building and even flown through a Swiss waterfall [source: Finighan].
Yet, I think, one of his craziest stunts was flying through a tiny crack in Tianmen Mountain in Hunan, China. Jumping from a helicopter swirling 6,000 feet [1,828.80 meters] overhead, the winged Corliss bailed out and flew like a Marvel Comic hero roughly 75 miles (120.7 kilometers) an hour through the mountain's 4,265-foot (1,299.9 meter) hole. No biggie, right? Um, the hole was just 100 feet [30.48 meters] wide. One wrong shrug of the shoulder, one errant breeze, would have pushed Corliss into the mountain's side. You have to see this to believe it.