Tokyo is among the 'megacities' forecast to exceed populations of fifteen million by 2020. The Millennium Tower challenges assumptions about such future cities and presents a solution to the social challenges of urban expansion on this scale and the particular problems of Tokyo, with its acute land shortages. It provides a million square metres of commercial development, stands 170 storeys high and is the world's tallest projected building.

Rising out of Tokyo Bay, the tower is capable of housing a community of up to 60,000 people, generating its own energy and processing its own waste. A vertical city quarter, it would be self-sustaining and virtually self-sufficient. The lower levels accommodate offices and clean industries such as consumer electronics. Above are apartments, while the uppermost section houses communications systems and wind generators. A high-speed 'metro' system − with cars designed to carry 160 people − tracks vertically and horizontally, moving through the building at twice the rate of conventional express lifts. Cars stop at sky centres at every thirtieth floor; from there, individual journeys may be completed via lifts or escalators. This continuous cycle reduces travel times − an important factor in a vertical city, no less than a horizontal one. The five-storey sky centres have different principal functions; one might include a hotel, another one a department store; each is articulated with mezzanines, terraces and gardens to create a sense of place.

Developed in response to the hurricane-strength wind forces and earthquakes for which the region is notorious, the tower's conical structure, with its helical steel cage, is inherently stable. It provides decreasing wind resistance towards the top − where it is completely open − and increasing width and strength towards the base to provide earthquake resistance. The project demonstrates that high-density or high-rise living can lead to an improved quality of life, where housing, work and leisure facilities are all conveniently close at hand.

Sketches + Drawings


Facts + Figures

  • Appointment: 1989
  • Area: 1,040,000m²
  • Height: 840m
  • Capacity: 50,000
  • Client: Obayashi Corporation