Architecture firm Skidmore Owings and Merrill has unveiled plans to build an 83-storey supertall skyscraper on the site of Donald Trump's old Grand Hyatt hotel in New York. Called 175 Park Avenue, the mixed-use tower will be 1,646 feet tall (500 metres) and contain office and retail space along with a new 500-room hotel run by hoteliers Hyatt. The glass and steel tower will replace the Grand Hyatt New York, originally built in 1919 as the Commodore Hotel and purchased in 1980 by Trump. The former US president renovated the hotel and enclosed the structure in dark glass for his first major construction project in the city.