The world's tallest tower, developed by Emaar Properties, was unveiled at Dubai on January 4th 2010.
The official height of the tower, unveiled as 'Burj Khalifa', was announced as 828 metres (2,716.5 ft).
Burj Khalifa is the tallest building in the world according to the three main criteria of the Council on Tall Buildings and Urban Habitat (CTBUH). The CTBUH ranks the world’s tallest buildings based on ‘Height to Architectural Top,’ ‘Height to Highest Occupied Floor’ and ‘Height to Tip.’
At 828 metres (2,716.5ft), Burj Khalifa is 320 metres taller than Taipei 101, which at 508 metres (1,667 ft) had held the record for the world’s tallest building measured to the architectural top since 2004, the year the project was announced.
Burj Khalifa achieved the distinction of being the world's tallest structure – surpassing the KVLY-TV mast (628.8 metres; 2,063 ft) in North Dakota, USA – 1,325 days after excavation work started in January 2004.
The tower also beats the 31-year-old record of CN Tower, which at 553.33 metres (1,815.5 ft) had been the world’s tallest free-standing structure on land since 1976.
Burj Khalifa employs a record-breaking 330,000 cubic metres of concrete, 39,000 metric tonnes of steel rebar and 142,000 square metres of glass; and it took 22 million man hours to build.
Other world records for Burj Khalifa include the highest occupied floor in the world, at over 550 metres (1,800 ft); the highest outdoor observation deck in the world – At the Top on Level 124; and the tallest service elevator, which travels to a height of 504 metres (1,654 ft).