One World Trade Center building, which is under construction on the site of the destroyed original World Trade Center
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Freedom Tower becomes NYC tallest building

One World Trade Center has become New York's tallest building, overtaking the Empire State Building, after a steel column was lifted into place.

The installation of the girder on the 100th floor of the skyscraper makes the structure at the site of the 9/11 attacks 1,271ft (387m) high.

The building, construction of which began in April 2006, will be 1,776ft tall when completed.

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