Parallel Cities : Walker Art Center : 9781935963127 : 1935963120 : 08 Sep 2016 : Parallel Cities examines the history of the multilevel city with a focus on elevated pedestrian systems as a recurrent concept in urban planning and design. The book chronicles the evolution and migration of this concept from 19th-century French social utopian thinkers and 20th-century Soviet Constructivist architectural circles to its incubation in postwar London, its theorization by members of CIAM and Team 10, and its eventual dissemination to North America and Asia, where extensive systems were built in cities such as Minneapolis, Calgary and Hong Kong. This fascinating and untold history explores an architectural idea as it evolves under varying social, geographic and political contexts-charting its use as an ever-shifting multipurpose tool to segregate or commingle the classes, foster social cohesion and the public good, facilitate security and surveillance, improve pedestrian safety and traffic flow