Every year, people risk their lives to enter places the world has marked off-limits, and in most cases, no one fully understands why. From the psychological forces that compel climbers to press on through the Death Zone of Mount Everest, to a stretch of New Mexico wilderness where at least 15 people have vanished without a trace, to a remote island in the Indian Ocean where trespassers are killed on sight - what is it about the world's most dangerous places that makes them impossible to resist?
