ABSTRACT
As the last chapter illustrated, regional urban networks link nearby cities into a functional metropolis. This chapter takes a geographically wider view to examine how national urban networks link entire metropolitan areas together to form national urban systems. For example, the Los Angeles metropolitan area is linked to the Chicago and New York metropolitan areas, which together form the backbone of the U.S. urban system. National urban networks can link metropolitan areas to one another in a variety of ways: transportation and communication linkages such as airline traffic and telephone calls keep people and information moving around the country, while finance and trade linkages facilitate the flow of investments and goods. These networks of exchanges between cities are important because they provide a structure for the activities of whole nations. Even small changes to national urban networks can radically alter the trajectory of a country, its cities, and their residents.
