The $70 million New York penthouse for those with a cosmopolitan world view

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  The penthouse went on sale in 2015 and the fit-out was completed last year. It has an asking price of $70 million. Courtesy Hayes Davidson and James Euwing

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  Above, inside the 10,000-square foot duplex penthouse on the 42nd and 43rd floors at 50 United Nations Plaza. Courtesy Hayes Davidson and James Euwing

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  The 50 United Nations Plaza is the first residential tower in the United States designed by Foster + Partners. Courtesy Hayes Davidson and James Euwing

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  The penthouse at 50 United Nations Plaza offers sweeping vistas of the East River, UN Secretariat, the Empire State Building and Chrysler building. Courtesy Hayes Davidson and James Euwing

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  The penthouse at 50 United Nations Plaza offers sweeping vistas of the East River, UN Secretariat, the Empire State Building and Chrysler building. Courtesy Paul Warchol

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  The seven-bedroom, seven-bathroom property has been put on the market for $70 million. Courtesy Anastassios Mentis

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  The penthouse at 50 United Nations Plaza offers sweeping vistas of the East River, UN Secretariat, the Empire State Building and Chrysler building. Courtesy Anastassios Mentis

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  The penthouse at 50 United Nations Plaza offers sweeping vistas of the East River, UN Secretariat, the Empire State Building and Chrysler building. Courtesy Anastassios Mentis

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  The 50 United Nations Plaza is the first residential tower in the United States designed by Foster + Partners. Courtesy Anastassios Mentis

The new 50 United Nations Plaza sits on a site across from the United Nations Headquarters. The Headquarters site was once owned by William Zeckendorf, Sr.

Last year, on the 60th anniversary of the opening of the UN building, Mr Zeckendorf’s grandsons William Zeckendorf and Arthur Zeckendorf completed the fit-out of 50 United Nations Plaza – a 167 metre-high, 43-storey luxury apartment tower that is the first residential tower in the US to be designed by British “starchitect” Norman Foster.

Their company, Zeckendorf Development, completed the project in a joint venture with Global Holdings.

It is a very grand building. The lobby has a floor to ceiling 20-foot water wall and a circular fireplace, and the building has a health and fitness centre with a 75ft-long pool, a conference room, a playroom and a landscaped motor court.

The building has just 88 apartments on its 43 floors, with the most spectacular being an almost 10,000 sq ft duplex penthouse on the 42nd and 43rd floors.

The seven-bedroom, seven-bathroom property has its own infinity-edge swimming pool, a handcrafted, 10,000 pound (4,535 kilogram) steel staircase and a 75ft-long main living room offering views of the East River, the UN Secretariat, the Empire State building and the Chrysler building.

There is also a bridge linking the master bedroom lounge and an entertainment lounge that has its own gas fireplace and catering kitchen.

The penthouse went on sale in 2015 and the fit-out was completed last year. It has an asking price of US$70 million. Jill Mangone, the director of sales at Zeckendorf Marketing, said: “We are extremely proud of the completed duplex penthouse which represents a residence using the highest quality materials and finishes, with a full array of amenities for the most discerning buyer.”

q&a a window over New York

Jill Mangone, the director of sales at Zeckendorf Marketing, on 50 United Nations’ penthouse, the building and the site:

What’s the history of this site?

After outgrowing its headquarters on Long Island, William Zeckendorf Sr read that the UN was considering relocating outside of New York. Emphatic that such a global organisation belonged in New York, he assembled the land where the United Nations headquarters stands now and subsequently sold the land to John D Rockefeller Jr, who then donated it to the UN. Decades later, Zeckendorf Sr’s grandsons acquired the land on which they built 50 United Nations Plaza.

Can you explain the concept behind its design?

According to Norman Foster, the chairman and founder of Foster + Partners, “The slender proportion of 50 United Nations Plaza is attenuated by the vertical stacks of bay windows, which give it a distinctive identity. From the apartments within, these bays offer spectacular views of the East River and Manhattan’s skyline. The polished stainless steel detailing of the facade is in the spirit of earlier historic towers in the city, and it reflects the sharp quality of light which is special to New York.”

What happened to the previously planned $100m triplex for the top of this building?

The original intent was to offer the duplex penthouse with the option of combining it with the full-floor penthouse directly below it for prospective buyers looking for added space. Combined, the two units would have cost $100m.

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