Completion of the Burj Khalifa

The Burj Khalifa is a supertall skyscraper in Dubai, designed by the Chicago based firm Skidmore, Owings and Merrill with Adrian Smith as chief architect and Bill Baker as chief structural engineer, whose buttressed core structural system allowed the tower to reach unprecedented height without excessive sway. Construction began in January 2004, the exterior was topped out in October 2009, and the building officially opened on 4 January 2010, initially under the working name Burj Dubai before being renamed in honour of UAE President Khalifa bin Zayed Al Nahyan. Reaching 829.8 metres including its spire, it became the tallest building and tallest freestanding structure in the world upon its full inauguration in 2011, surpassing Taipei 101 by a wide margin. Its Y shaped floor plan, tapering silhouette and hexagonal core were engineered specifically to reduce wind loads at extreme height, an innovation that influenced subsequent supertall design worldwide. The tower anchors the wider Downtown Dubai development and symbolises Dubai's rapid transformation into a global city, cementing the shift of record setting skyscraper construction from North America and Asia to the Gulf.