Scaling 121 stories of steel girders takes nerves of steel, as two unflappable daredevils - a Russian and a Ukrainian - recently proved by climbing Shanghai Tower and filming the vertiginous ordeal.

Donning army camos, black hoodies and face masks, Vadim Makhorov and Vitaly Raskalov evoke a Black Bloc aesthetic and an even more nonchalant attitude when readying themselves to scrape the sky with their own fingers.

While the two look the part for Project Mayhem, their only weapons are GoPros and DSLR cameras to capture what Raskalov described as a “f**king awesome” view from an airplane window.

As the self-styled ‘skywalkers’ approach three super-tall buildings in Pudong district underneath an overcast sky, one of them jokingly suggests, almost as an afterthought, “Hey, right now we need to think just how we’re going to climb this thing.”

screenshot from youtube video by user raskalovit

The ‘how’ soon becomes apparent as the pair sneak into the construction site for the world’s second tallest building under the cover of night, deftly avoiding detection by guards before giving the 2,073-foot (632-meter) structure a go.

The tower takes the form of nine cylindrical buildings stacked atop each other, curving 120 degrees from its base to its top to withstand the powerful winds which frequently blast through the city. Some of the more breathtaking scenes are captured just above the clouds, where the blinking lights of the Jin Mao Tower and Shanghai World Financial Center create scenes reminiscent of Blade Runner.

But vertigo really sets in when the duo scale the nearly 60 feet high crane perched atop the building. Without a rope or tricam in site, a firm grip on the crane’s lattice or grating is the only thing preventing them from engaging in an unplanned BASE jump.

"We had to wait for hours for the clouds to part but it was well worth the wait, the view was like something from an aircraft window,” Makhorov told Yahoo! News.

"As soon as we saw a gap in the clouds were climbed right to the top of the crane and were able to get some great shots of the city below."

screenshot from youtube video by user raskalovit

Raskalov said the hardest part of any climb is not the physical exertion or defying the fear of falling, but avoiding capture.

Writing for his blog, Makhorov said they specifically chose the Chinese New Year Season to attempt the climb, as security would be less vigilant and the crane would not be working.

“We got to the crane at around midnight. It took us almost two hours to get on the 120th floor on foot. And also, we spend almost 18 hours on top of the building, sleeping and waiting for better weather.”

This isn’t their first foray into skywalking, ‘roofing’ or other thrill seeking activities which put them at odds with local authorities.

Raskalov said the Shanghai Tower climb was in fact a relative cakewalk compared to their most difficult feat: scaling the spire on the main building of Moscow State University.

“Too many cameras. Too many guards,” Raskalov said.

The two also courted controversy last year by climbing the Giza Pyramids in Egypt, earning them a ban from that country. Raskalov was also imprisoned and later deported from Belarus for exploring the guts of Minsk’s Metro system. The 21-year-old Ukrainian has also been prohibited from returning to Russia for five years due to his death-defying stunts.

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