Chicago Approves Construction of 2,000ft Skyscraper

Chicago today moved a step closer to boasting the two tallest skyscrapers in the US when officials approved the construction of the 2,000ft Chicago Spire.

The building - designed by the Spanish architect Santiago Calatrava, the man behind the Milwaukee art museum's Quadracci pavilion - will be a twisting tower.

An apartment complex, the structure has been compared to a drill bit, a blade of grass or a tall twisting tree. It will incorporate a riverfront plaza and six levels of underground parking will be provided next to the site.

The $2.4bn (£1.2bn) tower will be made mainly of concrete, with its twisting exterior designed to deflect wind.

Located at the point where the Chicago River drains into Lake Michigan, it will be at the centre of a Chicago skyline that already features the black Sears Tower - currently the highest building in the US at 1,450ft.

The Chicago Sun-Times reported that buyers had already put down $20,000 (£10,090) deposits on 92 of the building's 300 apartments during a two-week promotion last year.

However, private financing for the project, to be built by Shelbourne Development, could prove the biggest hurdle to its completion.

Approval of the project shows that appetite for skyscrapers remains undiminished around the world despite the 2001 destruction of the World Trade Centre in New York. But in response to the September 11 terror attacks, the Chicago Spire has been designed with two emergency stairwells.

Experts say the craze for tall buildings is not just down to the boom for office property.

"Tall buildings are a matter of ego. Tall buildings are a sign of success," George Efstathiou, a managing partner at the architecture firm Skidmore, Owings and Merrill, told the Associated Press.

The practice is building both the new Freedom tower, on the World Trade Centre site, and the Burj Dubai, soon to be the world's tallest building.

The Burj Dubai's ultimate height is being kept secret, but developers say it will be at least 2,300ft, surpassing the current world's tallest building - the 1,671ft Taipei 101.

In London, the skyline in the city's financial district is dominated by the bulbous Gherkin building, and the green light has been given for the Shard of Glass, a 1,000ft tower designed by the Italian architect Renzo Piano.

However, building in Europe and the US is eclipsed by the frenzy in Dubai and China, where seven of the world's 10 highest buildings are to be found.