Construction crews set in place a steel horizontal beam at a height of about 1,270 feet, topping by about 20 feet the rooftop of the observation deck of the Empire State Building, which stands about 3 miles (4.8 km) to the north in Midtown Manhattan.
Including the antenna tower, however, the iconic Empire State Building is still higher.
The Empire State Building, built in 1931, was the city's tallest at a height of 1,545 feet to the tip of its broadcast antenna until 1972 when it was overtaken by the original World Trade Center towers. It then regained the title after the September 11, 2001, attacks, which destroyed the complex.
Construction started six years ago on the new World Trade Center and now the skyscraper, formerly called the Freedom Tower, surpasses the top floor of the Empire State Building, Port Authority officials told reporters.
One World Trade Center will stand at 1,776 feet to the tip of its antenna when it is completed, possibly by late 2013. Then it will top the Empire State entirely.
Click here to view a time-lapse video of the World Trade Center construction. BD+C