Auckland 360 Skywalk, New Zealand
One of the most unusual walkways on our list, the Auckland Skywalk consists of a platform attached to the side of a skyscraper in the downtown area of New Zealand's largest city. What truly makes a stroll on this path extreme is that it has no railings. Except for the few places where it is connected to the building, both sides of the 4-foot-wide walkway are surrounded by nothing but air, with the ground more than 600 feet below. People wear full-body harnesses attached to safety lines and are led around the path by a guide.