Hundreds of spectators looked up to the sky on Monday as daredevil climber Alain Robert worked his way up the side of Dubai’s 2,716-ft. (828 m) Burj Khalifa in just over six hours.
The 48-year-old hoisted himself up along the central column of the mostly glass and steel structure with ease, using the harness that was tethered 100 stories above ground only as a safety measure.
(More on TIME.com: See more about Alain Robert.)
Wearing a harness was unusual for the veteran climber, who has scaled more than 70 skyscrapers all over the world without any form of safety gear. In fact, the rope, which reassured most people, made the climb more stressful for Robert.
“There is huge pressure on me because I know that they have installed everything there; this is for me,” he told the Toronto Sun before the climb. “There is a giant screen, 50 meters high, 30 meters long. I know everybody is going to look at me, so it’s a bit of — a lot of — stress in fact.”
More on TIME.com: See pictures of the Burj Khalifa.
Watch Robert scale the tower: