People terrified after seeing waterslide that had no air inside it

A water slide without air is the type of ride that would make someone who isn't claustrophobic become claustrophobic.

The Tiki Pool at Duinrell holiday park is one of the Netherlands' most famous waterparks and the indoor/outdoor play area is known for its thrilling slides.

However, back in 1994, it was home to arguably the 'scariest slide of all time'.

The Fly Over was the world's only underwater water slide, which is exactly how it sounds.

To access the ride, swimmers would have to dive underwater and let gravity transport them upwards through the airless slide for around 15 to 20 seconds.

Viewers have been cringing at the footage. (Tobias Schefe)

"Imagine a water slide with no air and only water inside, one that sucks you through it, like Augustus Gloop in Willy Wonka & the Chocolate Factory," explains YouTuber Theme Park Crazy.

"It sounds terrifying, but it actually existed.

"Riders would enter a pool and dive underwater towards the slide's entrance.

"They would then be sucked up into the slide and taken through it before ending up in another pool, like me when I first found out about it, you may be wondering, 'How such a slide is even possible?'"

The YouTuber continued: "The answer is science, specifically, this phenomenon is known as the Communicating Vessels Principle.

"This principle dictates that water can easily be transferred between containers through a tube, thanks to the forces of gravity and air pressure.

"This will work just as long as the second container's water level is lower than the first.

The ride was eventually discontinued. (Tobias Schefe)

"So since the second pool's water line was lower than the first, guests would naturally be sucked right through the slide.

"As a safety measure, the slide was capable of draining at around five seconds if riders got stuck."

Although there was said to be a lot of public backlash at the time, that's not the reason why the ride was discontinued in 2010.

"Eventually, this slide became far too expensive for the park to operate," the YouTuber said.

"Most riders were terrified of the very idea of the slide, so it didn't receive a high ridership, plus concerns over panicking and inhaling water before the slide could drain, was reportedly a deciding factor as well."

Taking to Reddit, one rider claimed: "I went through it once when I was around 12 years old. I did not know what was going to happen in that slide, no signs or anything that warned you about it. At least not that I saw. Those were the longest 10 seconds of my life."

"Same here, tried it once at about that age. No warning, no escape. The water didn't flow fast enough, so I had to swim to get through. That was a near death experience. And a big nope, not ever again," a second added.

While a third commented: "That’s the stuff nightmares are made of."