Watch this incredible wingsuit flight through a tiny cave opening (VIDEO)

Alexander Polli is a professional BASE-jump athlete. But his latest video showcases a critically dangerous stunt, as Polli flies his wingsuit through a tiny opening in a steep mountainside.

The opening itself is barely wide enough for Polli to walk through, let alone attempt a life-threatening aerial maneuver at 150 mph.

But he wouldn’t be a famous BASE jumper if he wasn’t willing to try something extreme. Besides, Polli said the Roca Foradada Mountains in Montserrat, Spain, have inspired him throughout his life.

To prepare for the flight, Polli performed two test jumps in which he flew through a banner marked “2013.” In the first test, he hit the side of the banner. It was an impressive display of accuracy, but had it been the actual cave, it almost certainly would have been a fatal error.

In the second jump, he ripped perfectly through the center.

With a successful test flight completed, Polli stepped up for the real thing, launching from a helicopter with a camera mounted on top of his helmet to give viewers a first-person perspective as part of a project for EPIC TV.

And in a thrilling video clip, Polli in fact successfully navigates through the opening, as multiple cameras capture his accomplishment from different angles.

More than two million people have already watched the flight in less than 48 hours since it was posted to Polli’s YouTube account.

Still, that hasn’t stopped several commenters from accusing Polli of orchestrating a hoax.

"It honestly makes me verrry happy when people think it's fake," Polli wrote on his Twitter account.