The world’s tallest building Burj Khalifa took five years to build, is more than 160 floors high and has comfortably surpassed the previous record holder in Taiwan, the Taipei 101. More than 12,000 people will occupy its 6 million square feet, zooming up and down in 54 elevators that can reach speeds of 40 miles an hour. It will have the world’s highest mosque, on the 158th floor; the world’s highest swimming pool, on the 76th floor; the highest observation deck, on the 124th floor; and the first hotel by the fashion designer Armani. Burj Khalifa also claims to hold several other world records, including: tallest free-standing structure in the world (previously held by Toronto’s CN Tower); elevator with the longest travel distance in the world and most number of stories in the world. Adrian Smith, designer of the Burj Khalifa said he tried to blend the Islamic and modern Western architecture for the tallest tower.