It has inspired every giant city-centre complex in modern America, including those in Detroit, Atlanta and San Francisco.
The duo are currently trying to turn the disused St Paul's hospital into an art centre complex, complete with the latest recording and editing technology.
With time it has become part of the city's convention centre complex and through its distinctive architecture offers a counterpoint to the commercialised, nondescript towers surrounding it.
The rebels lack the firepower to breach the heavily fortified research centre complex and the compound is being used to shell Barzeh, the sources said.
Only 15 of its 41 floors have been dismantled.In contrast, Building 7 of the World Trade Centre complex was quickly rebuilt and reopened last year.
About 40,000 people normally worked in the twin towers, and around 150,000 visitors passed through the World Trade Centre complex each day.
The project has been inspired by the grand museums on South Kensington's Exhibition Road and the Southbank Centre complex, both born out of major national events: the 1851 Great Exhibition and the 1951 Festival of Britain.
Firefighter Rudy Weindler spent nearly 12 hours trying to find survivors but found only four - a pregnant woman sitting on a curb and three others in the rubble of the trade centre complex.
One of the most ambitious projects is Miami Worldcenter, a 30-acre retail, hotel and convention-centre complex that will feature Bloomingdale's, Macy's and a giant Marriott hotel.
Urban renewal and revitalization dramatically changed the central business district of the capital, with the construction of new shopping complexes, office buildings, sports centres, university facilities, and hotels; a major professional sports stadium in the city was demolished (to make room for an expanding convention centre complex), and a new stadium opened in 2008.
