Height: With the installation of the beacon, the tower will stand at 1,776 feet, representing the year the United States won independence from Great Britain. This will make it the tallest building in the Western Hemisphere – but dwarfed by Dubai's Burj Khalifa at 2,717 feet.
Why the beacon?An LED-powered light will be seen from kilometres away, helping to ward off aircraft.
And the spire?It will provide public transmission services for television and radio broadcast channels.
Spire weight:800 tons
Space:104 storeys; 3 million square feet of office space, an observation deck, shops and restaurants
Anchor tenants:Tony publisher Condé Nast (Vanity Fair, Vogue, New Yorker); General Services Administration (U.S. government agency); Vantone Holdings China Center
Architect:David Childs of Skidmore, Owings and Merrill
Editor's note: A May 2nd news article on the World Trade Center incorrectly said the United States won independence from Great Britain in 1776. In fact, while the U.S. declared its independence that year, it was not won officially until 1783.