NEW YORK -- One World Trade Center already is New York's tallest building.
And when the last pieces of its spire rise to the roof on Monday - weather permitting - the 104-floor skyscraper will be feet from becoming the highest in the Western Hemisphere.
The Port Authority of New York and New Jersey says the spire pieces plus a steel beacon will then be lifted at a later date from the rooftop to cap the building at 1,776 feet.
The new high-rise replaces the twin towers destroyed on Sept. 11, 2001.
The 408-foot spire will serve as a world-class broadcast antenna.
The new tower is at the northwest corner of the World Trade Center site, which is well on its way to reconstruction with the 72-story Four World Trade Center and other buildings.