Perhaps the most perceptive and surprising observation in Reyner Banham’s Los Angeles: The Architecture of the Four Ecologies comes in the chapter “The Transportation Palimpsest,” in which he argues that Los Angeles’s radical decentralization was not the product of the automobile and the freeway but of its earlier streetcar network. It was Pacific Electric’s 1,000-mile transit system that, by the 1920s, first connected the vast Los Angeles basin and established the region’s uniquely spread-out pattern of development.