Surfing across turquoise water below wax-like stalactites and bulbous rock formations, you might get the impression that Dutch wakeboarder Duncan Zuur is performing in front of a green screen. But the cave system he rode over wasn't a CGI creation – it's an actual place called Jeita Grotto and is the longest cave in the Middle East.

Located in Beirut, Lebanon, the Jeita Grotto is comprised of two connected cave systems, the Upper Grotto and the Lower Grotto. Altogether the limestone caves stretch across nearly 5.6 miles in the Nahr al-Kalb valley. Because the lower grotto is filled with an underground river, visitors can tour the cave by boat, says the Jeita Grotto website.

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When wakeboarder Duncan Zuur visited the grotto in December 2013, he performed heart-stopping jumps on ramps that were set up specifically for the occasion. The Red Bull sponsored athlete worked closely with the site curators to illuminate the caves and capture the scene without damaging the rock formations.

"I stopped thinking about riding because there was so much beauty from a world I've never seen," Zuur said of his experience in the caves, reported the BBC. 

Check out Zuur's mind-blowing performance in the slideshow above, and be sure to stop by the Jeita Grotto if you're ever in Beirut.