Parallel Lines

Abstract

This chapter focuses on urban expressways in American cities, as distinct from the system of which they are part. The passage of the Federal Aid Highway Act of 1956 marked the culmination of a long process to establish what would become the Interstate Highway System. Starting in the nineteenth century, a series of events outlined the need for and scope of a potential network, while the technological, financial, and social developments starting at the dawn of the twentieth century transformed the underlying logic and objectives of a national road system. Originally intended to operate on the abstract grid of territory, the system instead became a network of connections between urban centers. Understood in this context, the development of the urban expressway followed two parallel lines. One line was drawn by governmental institutions, civic associations, and private capital, beginning in the nineteenth century, as a reaction to a changing urban environment. The other was constructed through a series of government documents produced in the first half of the twentieth century, debating the proper form and institutional frame of a modern national road system and its relation to the city. From this perspective, the urban expressway was the result of the convergence of these once-parallel lines, radically transforming the postwar American city and the meaning of the urban itself.