The World's New Tallest Building

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Fireworks explode around the Burj Khalifa during the opening ceremony. Initially known as the Burj Dubai, Sheikh Mohammed bin Rashid al-Maktoum, Dubai's ruler, renamed the tower Burj Khalifa after the President of the United Arab Emirates, Sheik Khalifa bin Zayed Al Nahyan, whose country has lent Dubai billions of dollars in the past few months.

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