Towering more than 160 stories over the Middle East business hub of Dubai, Burj Khalifa, the tallest building in the world, stands at 2,723 feet tall — almost two times the size of Chicago's Willis Tower (1,451 feet). Construction began in late 2004 and took a little more than five years to complete, with its official opening in January 2010. The skyscraper was created by the government to shift Dubai's economic focus from oil, garner more international recognition and make it a destination for service and tourism. In addition to corporate suites, a restaurant and a 124th-floor observation deck, Burj Khalifa houses the Armani Hotel Dubai in its bottom 39 floors, consisting of 160 guest rooms and suites and 144 residences. Although its completion coincided with a global financial crisis, Burj Khalifa was successful in attracting more attention as BASE jumpers, climbers and even Tom Cruise came to conquer the structure's towering heights — with Cruise performing his own stunts for the fourth "Mission: Impossible" installment, "Ghost Protocol." The building has even started collecting awards and has become internationally recognized as an architectural icon, due to the work of Skidmore, Owings and Merrill of Chicago, with Adrian Smith as chief architect.
One World Trade Center in New York City is next on the list at 1,776 feet. Taipei 101, at 1,671 feet, was the tallest building in the world from 2004 until Burj Khalifa's opening, followed by the Shanghai World Financial Center — nicknamed the "Bottle Opener" — at 1,614 feet with the Park Hyatt Shanghai on floors 79-93. Next are the International Commerce Centre in Hong Kong at 1,588 feet (home to The Ritz-Carlton, Hong Kong) and Petronas Towers in Kuala Lumpur at 1,483 feet.