In the United States,a giant, highly urbanized area stretches in a 500-mile-long band along the East Coast and includes many financial centers." Megalopolis" is the name for this band of urbanization applied by the French geographer Jean Gottman. It begins with Boston, Massachusetts, on the New England coast and stretches south and west across portions of ten states, through New York City, Philadelphia, and Baltimore, teminating south of Washington D.C. Megalopolis encompasses not only these five cities but many other adjacent, smaller cities. It covers less than 2 percent of the area of the United States, yet contains nearly 20 percent of its population.

Gottman's first main insight was that this vast urban area was not a single, very large city Rather, Megalopolis is composed of multiple independent urban nodes (heavily populated areas with a high concentration of activity), whose outer fringes have grown together. There is no center, no centralized network of services, no shared governmental institutions. In fact, this region crosses tens of thousands of administrative units, from national to local. The one common experience shared by its residents is urbanness-including high overall population densities that intensify toward city interiors. Its residents must accept crowding, traffic congestion, and high costs of living (especially for housing) but they enjoy lots of choices in occupations, housing, neighborhoods, social activities, restaurants shopping, entertainment, education, and employment.

Yet Megalopolis also contains rural landscapes where famers may produce high-quality specialty foods for the cities. The absence of unifying government, Megalopolis is tied together mainly by its transportation system; 30 percent of the United States export trade passes through its six main ports along the northeastern seacoast, while its residents rely on a network of interstate highways,railways, and airways superimposed on a complex web of local streets and roads.

Gottman observed that this urban region was, at the time of writing (in the 1960s), a unique phenomenon in human history. Yet his second main insight was that it was likely to appear elsewhere in the world. His prediction has come to pass. There are now several such areas around the globe, including in Japan, Brazil, and Mexico.

Why did Megalopolis develop where it did? The answerlies both in its site (its actual location on the East Coast) and situation (its location relative to other land features) First of all, the northeast has a particularly irregular coastline, with many protective peninsulas and deep-water inlets that are now useful seaports. The surface features inland are also a key to modern use. Many of the biggest United States cities developed along rive just where the foothills of the Appalachian Mountains meet the rather narrow coastal plain. The abrupt change in elevation created unnavigable falls and rapids, the fall line. Oceangoing shipping could gonofartherwest, so goods had to be off-loaded to other means of transportation: this led to a demand for warehouses and laborto shift cargo. The fall line also created a natural waterpower source where grain could be milled and lumber sawed.

The situation of Megalopolis relative to other places also contributed to its long and complex pattern of growth. The farms and settlements in the vast interior of the continent created a market for all kinds of manufactured products shipped through Megalopolis first from Europe and later from other points in the Americas. Agricultural products from the interior farms found their way into the world market through the coastal cities. Meanwhile, the cities of Megalopolis produced their own products and ideas for global exchange. Thus, the location of these cities on the edge of a massive and rapidly developing continent provided an unusually rich environment for long term growth.

Today, Megalopolis has to contend both with the results of its own incredible long- term success and with changing patterns of world production and trade. Because it developed early, much of its built environment is now in decline, including its infrastructure of industrial plants, power and other utilities, waste-treatment plants, facilities and interurban rail and interstate-highway transport systems.Because industrial competition is increasing globally, the cities of Megalopolis have to deal with shrinking earnings just when they need to levy taxes to rebuild and update the infrastructure that will keep them competitive.