World-renowned climber Alex Honnold has completed the largest urban free-solo climb in history. On Saturday, January 24, during a live special broadcast on Netflix, he scaled the exterior of Taipei 101, a 508-meter (1,667-foot) skyscraper, without ropes or safety equipment, finishing the ascent in less than 90 minutes.

The climb began at 9:17 a.m. local time in Taiwan and marked the first-ever free-solo ascent of a skyscraper. In a previously aired interview, Honnold said Taipei 101 had fascinated him for years and that he had dreamed of climbing it for about 12 years. The challenge unfolded in three stages: first, a 113-meter sloped steel-and-glass section; second, eight “bamboo box” structures with overhangs; and finally, the spire, which posed the toughest physical test.

Honnold’s heart rate reportedly reached about 165 beats per minute halfway through. He ended the climb by taking a selfie at the summit. The successful, accident-free feat drew widespread global praise.