What’s the underwater sign for “mind blown”? These H2O-fueled fantasies wow even the most seasoned bubblers with their ingenuity, engineering and design.

Cirque Du Soleil's “O” —Las Vegas

It’s hard to capture the magic of “O” without setting eyes on the theatrical masterpiece of dancing water, acrobatics and aerial feats, which largely rely on a helpful team of scuba pros under the surface of an intricately designed set.

“The stage floor has seven individual lifts that can move independently of each other or in unison,” says Alan Williams, head of aquatics. “These lifts create shifting depths from 17 feet deep to 1.4 feet above the surface, within different stage sections throughout the show, depending on the storyline and performers’ needs. In one moment, a dancer could skitter across the water’s surface, while in the next, a plunging high diver could nosedive into that same spot. Even a normal set featuring a shifting floor would be challenging if not dangerous to perform upon and within—adding up to 17 feet of water to the mix adds to the peril.

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“Keeping the cast safe requires training each technician of the hazard points during the show,” says Williams. “We use an underwater speaker system to notify the divers of any irregular stage movements. Safe edges are in place where pinch points are present. A console operator watches overhead and with in-water cameras. Communication divers watch and relay alerts of any divers that are in a hazardous position.”

“O” employs 14 certified diver techs to help with staging and props, and four artist handlers, who must carry a PADI Divemaster or higher rating. Performers don’t wear scuba gear; they dive down to use one of 78 regulators attached to a hookah system or, in the case of synchronized swimmers, swim to one of three second-stage regulators or spare pony bottles carried by their artist handler. All cast members must be certified.

“Once they complete their scuba training, the performers rehearse each of their acts until they are ready for staging to be put into the show,” says Williams.

This perfectly choreographed splash of a performance depends on the dive crew’s expertise and the reliability of the show’s compressed-air supply.

“Diver technicians utilize one tank per show, plus we have two pony bottles for use when an artist handler must assist more than three artists at one time. A 2,500-cubic-foot bank system feeds the hookah system in the pool. It is connected to a compressor that automatically refills the system when it gets low.”

To say the show is popular is an understatement. Over 19.6 million viewers have enjoyed 11,600 shows since its debut at Las Vegas’ Bellagio. Keep an eye out for a brief—but memorable—curtain call by the dive team.

Jules’ Undersea Lodge—Florida Keys

At first glance, this underwater hospitality venue seems like a quirky tourist photo op primed to be splashed across social media, but “Jules” has a far more impressive history.

“Jules was a research station that was built in the late 70s and taken to Vazquez, Puerto Rico, in the early 80s,” says Teresa McKinna, president of the Lodge. “She was put down about 80 feet. During the time they were doing their research, Puerto Rico Inter-National Undersea Laboratory (PRINUL) did over 800 important marine biology and body physiology studies. They had astronauts at the station, too. They were doing both physiology and psychological studies of people being alone, such as the case would be in a spacecraft.”

Once the studies were completed, the station was transported to Miami and refurbished into a fully outfitted habitation to allow the public to see what it would be like to live underwater.

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Jules is submerged in a 2.5-acre Florida Keys lagoon between 29 and 31 feet deep, depending on the tide. Regardless of the shallow depth, no matter how long the stay, the lodge suggests avoiding diving and flying for 24 hours after a visit. Alcohol is also prohibited during a stay.

“For entering the facility, we have what’s called the ‘moon pool,’ christened as such by the astronauts when Jules was in Vazquez,” says McKinna. “Puerto Rico’s very white sand reflected the light from a full moon up into the entrance. There is pressure from air being pumped into the hotel, which pushes the water level down, so it keeps the interior dry.”

Divers swim underneath the hotel up onto a platform, where they remove their scuba gear, take a shower, put on dry clothes and enjoy dinner or leisure time. They can even livestream or chat with friends using Jules’ underwater internet, watch movies or play board games.

McKinna explains that everything is transported in boxes. “You can imagine, it is very difficult to change out an air conditioner, a refrigerator, a microwave, a TV. It’s not like we have a delivery from Home Depot roll up.”

Visits can be overnight or as short as three hours. The history and scientific attributes of Jules have inspired the unique PADI Aquanaut specialty course.

“The aquanauts in the 1980s stayed 24 hours. That’s why our PADI course is called the Aquanaut specialty. It’s a 24-hour program where you dive in, learn the concept behind the station and do three dives in the lagoon direct from Jules without surfacing.”

Far from a desolate landing spot for the station, the lagoon is a popular dive site in its own right whose protected waters offer a bimonthly location for PADI Instructor Development courses and a sidemount training destination.

“Puerto Rico’s very white sand reflected the light from a full moon up into the entrance. There is pressure from air being pumped into the hotel, which pushes the water level down, so it keeps the interior dry.

“In 2023, we had a commander in the Navy who stayed inside the hotel for over three months. He was also a hyperbaric specialist. He did 100 days in the hotel, and they did all kinds of body physiology studies on him. They had marine scientists specializing in different things join him on dives or visit him in the station. Our lagoon has quite a lot of sponges, and the marine biologists found two new species of sponges never before seen.”

Related Reading: https://www.scubadiving.com/could-you-live-underwater-for-100-days

Deep Dive Dubai—United Arab Emirates

For anyone who has visited Dubai, the fantastical and fabulous often go hand in hand. It’s no surprise that the deepest pool in the world, designed for divers, would be located here—even if it happens to be in the Arabian Desert.

“Digging a 60-meter hole in the desert was an engineering challenge on its own,” says Jesper Kjoller, marketing manager of Deep Dive Dubai. “Also having so many different materials in the water and managing deterioration and galvanic corrosion proved difficult.”

Far from a typical rectangle, this 200-foot-deep pool is more akin to an underwater art exhibit or interactive movie set. Dropping down into an otherworldly landscape, divers swim through furnished apartment buildings, libraries complete with removable books and sliding ladders, art galleries, alleyways replete with motorcycles, and game rooms of billiards tables with perfectly weighted balls to play a quick round of eight-ball.

“A normal pool only has water and tiles,” says Kjoller. “We have concrete, bricks, composite materials and different metals, and they all interact. Electrical currents from lights, cameras and speakers accelerate the corrosion process, so we had to learn over the years what would work and, for example, that certain materials like aluminum are a no-go.”

Once the foundation of the pool was designed, tech elements for safety, such as an intercom communication system and an extensive camera system for monitoring divers throughout the facility, were added. A sound system added atmospheric music to the experience. An array of unique objects themed to each chamber’s interior offered divers a bevy of opportunities to connect with the underwater set as they kicked through each scene.

“A normal pool only has water and tiles,” says Kjoller. “We have concrete, bricks, composite materials and different metals, and they all interact.”

“We just make sure the props are negatively buoyant and anchored on solid platforms,” says Kjoller. “We have upgraded, changed and replaced or repaired props since opening. We installed more lights and upgraded camera systems as better technology became available.”

Maintaining a healthy, crystal-clear water column 200 feet deep was key.

“The filter system is based on six main pumps, each responsible for 10 meters of water column,” says Kjoller. “The pressure is not an issue at all. Water is not compressible, so it behaves the same on all depths.”

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