Views From Atop The Willis Tower [Getty Images]

A girl sits on the glass balcony at the skydeck of the Willis Tower in Chicago, Illinois, U.S., on Wednesday, Feb. 13, 2013. Willis Tower, formerly named the Sears Tower, is the tallest building in the U.S. and one of the most popular tourist destinations in Chicago with over one million visitors to its observation deck each year. Photographer: Tim Boyle/Bloomberg via Getty Images

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