U

Urban Decentralization

The diffusion of urban structures and functions outward from the urban core, or

Central Business District (CBD). This process has occurred to some degree in

metropolitan areas in the economically advanced countries because the advent of

mass-transit systems in the 19th century, when trams, street cars, railways, and

early subways allowed workers to live much greater distances from their places

of work than had previously been the case. The development of such lines of trans-

port allowed those with the economic wherewithal to relocate their places of

residence further from the compact city center, along the various radiuses of the

transportation network, resulting in a dispersion of city dwellers over a greater

space. Residential clusters on the outskirts of the city were labeled “sub urban

areas,” or simplysuburbs. As the customer base decentralized in urban areas, busi-

nesses also began to relocate to the suburbs, especially those that offered goods and

services that were low cost and purchased frequently, such as grocery stores,

barbers, clothing, etc. Land developers frequently worked in coordination with

transit companies, planning residential communities that would have ready access

to the transportation system, because many residents continued to work in the

CBD and therefore commuted into and out of the city on a daily schedule. In North

America, urban decentralization was spurred after the 1880s by rising standards of

living, advances in transportation technology, and rapidpopulationincreases.

The period of greatest urban decentralization in the economically developed

world occurred from the late 1920s to the 1970s. The affordability and convenience

of the automobile, especially in the United States, resulted in an intensification of

decentralization in metropolitan areas. After World War II, this movement became

even more pronounced due to several factors, including a high rate of family forma-

tion, the availability of relatively inexpensive loans for home mortgages, and most

importantly, the construction of the federal interstate highway system. Interstate

highways were originally conceived as conduits for troops and supplies to major

cities in the event of war, so the roadways were typically constructed directly

through the heart of the city, adjacent to the CBD. By the 1970s, interstate bypasses,

forming a loop around the city center, were common in manylocations. This trans-

portation geography led to the emergence of edge cities, so-called asylum suburbs,

and related features of a decentralized urbanlandscape. Economic functions were

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