Emaar started construction on its most ambitious project to date on 1998, the AED 73 billion (US$20 billion) Burj Khalifa Downtown development, which comprises the Burj Khalifa - the tallest tower in the world when completed in 2009, the Dubai Mall, Burj Khalifa Business Hub, The Lofts, The Old Town, The Old Town Island, Burj Khalifa Boulevard, The Residences, Burj Views, man-made lakes, landscaped parks and gardens.