TAIPEI, Taiwan (AP) — American rock climber Alex Honnold began his ascent of the Taipei 101 skyscraper on Sunday without any ropes or protective equipment.

Cheers erupted from a gathered crowd as he started climbing the 508-meter (1,667-foot) tower, using the horizontal metal beams to pull himself up with his bare hands.

The onlookers cheered again when he paused at one point and turned around to face them, in a red short-sleeve shirt that stood out as he made the climb.

Honnold’s free solo climb of the iconic building in Taiwan’s capital city was being broadcast live on Netflix with a 10-second delay. The ascent, originally scheduled for Saturday, was delayed for 24 hours due to rain.

The climb drew both excitement and concern over the ethical implications of attempting such a high-risk endeavor on live broadcast.

Honnold, known for his ropeless ascent up Yosemite National Park’s El Capitan, climbed up one corner of Taipei 101 using small L-shaped outcroppings as footholds. Periodically, he had to maneuver around and clamber up the sides of large ornamental structures that jut out from the tower.

The building has 101 floors, with the hardest part being the 64 floors comprising the middle section — the “bamboo boxes” that give the building its signature look. Divided into eight, each segment has eight floors of steep, overhanging climbing followed by balconies, where he was taking short rests as he made his way upward.

Honnold won’t be the first climber to ascend the skyscraper, but he will be the first to do so without a rope. French rock climber Alain Robert scaled the building on Christmas Day in 2004 as part of the grand opening of what was then the world’s tallest building.