Taipei, Taiwan - An American climber took on Taiwan's tallest building on Sunday, becoming the first person to scale Taipei 101 without a rope, harness, or safety net.

Hundreds of spectators gathered at the base of the 101-storey tower to watch Alex Honnold (40) embark on his daredevil feat, which was also broadcast live on Netflix.

After an hour and a half, he successfully made it up 1,667 feet before triumphantly rappelling down to reunite with his wife, Sanni McCandless Honnold.

Speaking at a press briefing afterwards, Honnold said "time is finite," and people should "use it in the best way."

Athletes Travis Kelce addresses retirement rumors after "embarrassing" NFL season

"If you work really hard... you can do hard things," Honnold added.

Honnold has conquered some of the world's most intimidating rock faces and rose to global fame in 2017 after he climbed Yosemite's "El Capitan," lauded among his peers as the pinnacle of technical difficulty on the massive granite monolith.

It had always been a dream of Honnold's to add scaling Taipei 101 to his list of achievements, he told reporters, adding that his first request had been rejected. He did not offer more details about why this was the case.

"For the project to come together more than a decade later... It's so great. What an opportunity, it is such a pleasure," he added.

Honnold is the first person to free solo climb Taipei 101, without a rope, harness, or safety net, but not the first to reach its peak.

In 2004, Alain Robert, dubbed "the French Spiderman," was the first to take on the challenge, but used safety ropes because of the rainy conditions.

Sunday's spectacle drew crowds of hundreds, with onlooker Richard Bode (34) calling the event a "once-in-a-lifetime experience."

Benson (24) told AFP that Honnold was "incredibly brave," while others, like Lin Chia-jou (54) said it was "terrifying" to watch.

Taiwan's President Lai Ching-te congratulated Honnold in a Facebook post on Sunday, branding the challenge "truly moving."

"The climb was tense, setting hearts racing," he added in the post.