The Nine Elms development on the south bank of the Thames has become a symbol for the growing divide in the London housing market.
And the huge project, which Boris Johnson pledged would help regenerate the area, looks set to get even more divisive after architects added a glass pool suspended 10 storeys above street level for the exclusive use of the block's residents.
Prices at Ballymore's 2,000-home complex Embassy Gardens are far above the reach of ordinary Londoners - the tiniest flats come with a price tag of more than £600,000.
Owners will have the use of a "world-first" concept pool, resembling a giant aquarium in the sky, that acts as a bridge between two blocks of apartments. The developers said that the pool would measure 90 feet by 19 feet, with a water depth of 4 feet. Eight inches of glass will keep swimmers from crashing down to Earth.
Homes at the Nine Elms development, described by the Mayor as "the most important regeneration story in London", have recently appeared in billboards and newspaper adverts across Asia.
It has led to concerns that the houses will be bought as overseas investments and sit empty, rather than being "the residential heart of London's newest neighbourhood" as the development is described by Ballymore.
Sean Mulryan, the chairman and founder of Ballymore, told Homes and Property he had come up with the idea for the pool, which will also be accompanied by a sky deck and bar for summer loungers.
He said: "We set out to create places and spaces that are more than just bricks and mortar. The pool is testimony to this philosophy and gives the development a unique character."
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