A view of Tokyo Skytree, the world's tallest broadcasting tower at 634 meters (2080 feet), in Tokyo on May 21, 2012. The tower opened to the public on May 22, with hundreds of people entering the tower and its large shopping mall. Kyodo/Reuters
The ceremonial last beam is hoisted to the top of Four World Trade Center, Monday, June 25, 2012. The 72-floor, 977-foot tower is scheduled to open late next year. It's expected to be the first tower completed on the 16-acre site since the 9/11 attacks. (AP Photo/Mark Lennihan)
Visitors wait in front of the entrance of the Tokyo Skytree in Tokyo, Tuesday, May 22, 2012. Itsuo Inouye/AP
One World Trade Center, the giant monolith being built to replace the twin towers destroyed in the Sept. 11 attacks, will lay claim to the title of New York City’s tallest skyscraper on Monday, April 30 as workers erect steel columns that will make its unfinished skeleton a little over 1,250 feet, just high enough to peak over the observation deck on the Empire State Building. Mark Lennihan/AP
An ironworker connects a steel plate to a column at One World Trade Center in New York, or “Freedom Tower”, in December 2010. The Empire State Building is visible in the rear upper left. Mark Lennihan/AP/File
A BASE jumper freefalls after jumping from the Jinmao Tower in Shanghai. Reuters/File
The Jinmao Building in Shanghai, China, is 1,381 feet tall and was built in 1999. Reuters/File
This computer-generated image shows the Shanghai Tower (r.), not finished, which will stand beside Shanghai World Financial Center (l.) which stands 1,614 feet tall, and Jinmao Tower (c.) in Lujiazui financial district of Shanghai. Gensler/Reuters
Shanghai's financial district skyline along the Huang Pu river in Shanghai, China, March 28, 2010. Reuters/File
A crane lifts a section of steel onto the top of the Shard building in central London, March 30, 2012. The final section of steel meant the Shard reached its full height of 1,017 feet, making it the tallest building in Europe. Toby Melville/Reuters
The Chrysler Building (r.), and The Empire State Building (l.), in New York. The Chrysler Building was New York's tallest from 1930-31, until the completion of the Empire State Building. Richard Drew/AP/File
The 1,260 ft tall skyscraper at Shun Hing Square in the southern Chinese city of Shenzhen in Guangdong province, China, was finished in 1996.
The Burj Khalifa in Dubai, United Arab Emirates, is the tallest building in the world. Completed in 2010, it stands 2,717 feet high. Charles Verghese/EMAAR/PRNewsFoto/File
Standing 1,670 feet tall, the Taipei 101 Tower in Taipei, Taiwan was built in 2004. Wally Santana/AP/File
Completed in 1998, the Petronas Towers in Kuala Lumpur, Malaysia, stands 1,483 feet tall. AP/File
On July 16, 2009, Sears Tower, the tallest building in the Western Hemisphere, was renamed Willis Tower after Willis Group, the global insurance broker, in a changing of the guard that underscores Chicago's increasing importance as a major global financial and business center. The Willis Tower is 1,450 feet high and was built in 1974. Business Wire/File
Finished in 2003, Hong Kong's Two International Finance Centre is 1,362 feet tall. Vincent Yu/AP
The Empire State Building in New York is 1,250 feet tall and was completed in 1931. Andy Nelson/Staff
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