The evolution of built landscapes in metropolitan regions

This article analyzes the evolution of built landscapes in six U.S. metropolitan regions using historic maps, aerial photographs, and GIS software. The analysis identifies seven main historic patterns of urban form and nine types created in the 1980-2005 period. This recent period was characterized by a proliferation and fragmentation of built landscape types, rapid spatial expansion, and falling densities. These trends raise the question of whether the public sector should more proactively shape urban form. Rural sprawl accounts for much of the land now being urbanized, representing a new planning challenge. The Portland Urban Growth Boundary is found to be effective at limiting this type of development. The New Urbanist neighborhood form is still extremely rare.