New York City's One World Trade Center is now the nation's tallest building

It's official: New York City's One World Trade Center is now the nation's tallest building, wresting the title from Chicago's Willis Tower, which claimed the top spot for 40 years.
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It also leapfrogged the 1,667-foot Taipei 101 in Taiwan to become the third largest building in the world.
Burj Khalifa, the 163-floor office, hotel and residential building in Dubai. continues to tower over all the rest in the world at 2,717 feet.

Willis Tower, formerly known as Sears Tower, had threatened to hold onto its top U.S. spot after a design change for the needle on top of the World Trade Center raised the question of whether it was part of the structure or an add-on, like an antenna or lightning rod.
The ruling Tuesday by the Height Committee of the Council on Tall Buildings and Urban Habitat, which is the final arbiter of global building heights, means the WTC building can claim its full 1,776-foot height.
The 1,776 figure is symbolically important for the tower that was built on the site of the Sept. 11, 2001, terror attacks.

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