Tokyo Bay millennium tower, c 1996.
© Science Museum / Science & Society Picture Library
Architectural model. At 840m tall, the Millenium Tower in Tokyo would have been twice the height of the Chicago Sears Tower. It was designed to hold 50,000 people and support a mixture of work and leisure activities. 'Town squares' every 30 floors would have divided the tower into localities similar to neighbourhoods, and high-speed lifts the size of buses would have carried up to 150 people through its helical steel structure. The tower was never built; it became a victim of the bursting of the real estate bubble in Japan in the late 1990s.