In pictures: Building the Dubai tower

Work on the 162-storey Burj Dubai - the world's tallest building - began in September 2004 and progressed rapidly.

The building took 22 million man hours and, at the peak of construction, involved some 12,000 workers, according to Reuters news agency. At times, new floors were reportedly being added almost every three days.

General view shows 29 January 2006 construction work

Building work began during Dubai's boom times and, when offices and apartments went on sale "off-plan" in 2004, most had been snapped up by local and international investors within two days.

It was designed to offer more than 1,000 residential apartments as well as 49 floors of office space and a hotel designed by Giorgio Armani.

By July 2007 it was 512m (1,680ft) tall - and had claimed the world's tallest building title from Taipei 101 in Taiwan. Its final height was announced as 828m (2,716ft).

It has also broken other records, boasting the world's highest observation deck, swimming pool, elevator, restaurant and fountain.

The building was designed by Chicago-based architect Adrian Smith, who said the ascending spires were an attempt to bridge the gap between Islamic tradition and ultra-modern Western architecture.

It is opening in times of economic uncertainty for Dubai, but the building's developers, Emaar, are confident for its future and say 90% of the building is sold.