The tallest structure in the world, standing at 2,722 ft (830 meters), just over 1/2 mile high, Burj Khalifa (Khalifa Tower) opened in 2010 as a centerpiece building in a large-scale, mixed-use development called Downtown Dubai. The building originally referred to as Dubai Tower was renamed in honor of the president of the United Arab Emirates, Khalifa bin Zayed Al Nahyan. Burj Khalifa – Dubai, United Arab Emirates