Alex Honnold just rewrote the limits of human endurance. The legendary American climber completed a free-solo ascent of Taipei 101 on January 25 CST, one of the tallest skyscrapers in the world, without a rope or harness, all while streaming live on Netflix. Battling smooth steel and glass instead of rock, Honnold reached the top in just over 90 minutes, setting the record for the highest urban free-solo climb ever attempted.