To call this a pool with a view would be an understatement. London, England will have what is reportedly the world's first sky-high 360-degree rooftop infinity pool in 2020.
The pool will be built on the roof of a 55-story building, situating the the 174-gallon pool 200 meters (or about 656 feet) in the air, according to designer Compass Pools.
The pool will also have a see-through bottom.
The pool will be part of a new luxury hotel, Infinity London, also slated to open by 2020, Alex Kemsley, the technical director and designer of the pool, tells CNBC Make It.
"We are expecting the pool itself to cost in excess of 10 million pounds," he says, which is $12.7 million.
The pool's transparent floor, which will allow visitors to see people swimming and sky above, will be made from cast acrylic (rather than glass) "so that the pool will look perfectly clear," according to Compass Pools. Acrylic "transmits light at a similar wavelength to water," causing the effect, says the company.
The mechanism to enter the pool is based on the door of a submarine, and it has a "rotating spiral staircase which rises from the pool floor when someone wants to get in or out — the absolute cutting edge of swimming pool and building design and a little bit James Bond to boot!" Kemsley said in a statement.
"Normally a simple ladder would suffice, but we didn't want stairs on the outside of the building or in the pool as it would spoil the view," he said.
A built-in "anemometer" that monitors wind speed will used to prevent water from blowing down to the street, according to the website, and the pool's heating system will use waste energy from the building's air conditioning system.
Though Infinity London's is set to the only 360-degree infinity pool on a rooftop, it won't be the only high-sky pool you can visit. Marina Bay Sands hotel in Singapore has a rooftop infinity pool on the 57th floor of the hotel (thought the views are not 360 degrees). It's 492 feet long and extends across three tower buildings and is billed as the "world's largest rooftop infinity pool," according to the website. It opened in 2010.
Marina Bay Sands was one of the 'Most Instagrammed Hotels of 2017," according to Travel + Leisure, which used number of geotags for the ranking.
In Houston, there is a glass-bottom pool 500 feet above ground at Market Square Tower Apartments, which opened in 2017.
The glass-bottom pool "cantilevered over the rooftop edge," according to the website, is on the 40th floor infinity deck, and is open to residents and guests of the luxury high-rise.
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