Geography Reference
In-Depth Information
Acropolis sites
, characterized by locally high ground, which is fairly easy to defend, have also been
favored. Examples include Quebec City, Albany (New York), and Athens, Greece — whose famous
Acropolis is the source of this category.
Peninsula sites
were also favored because a wall across a
neck of land, complemented by the surrounding water (a natural moat), greatly facilitated defense.
Boston and Bombay, also noted for their natural harbors, are good examples.
Because of these and other site-related factors, settlements developed at various locations around the
world. All were small at first. Many did not stay that way.
Getting Big: Urban Growth
At favored sites around the world, hundreds (if not thousands) of once-humble settlements have de-
veloped into cities of varying size. And the process continues. In fact, urbanization is not just a major
human characteristic, but also a major trend. But the pace of urban growth and the reasons for it are
not the same everywhere. Because space does not permit a truly global treatment of this truly global
process, I'm going to focus on a prime example of the urbanization process — the United States.
Much of the growth of American cities has been due to immigration and natural population growth.
But other factors have also encouraged cities to expand not just population-wise, but also with respect
to the physical area taken up by them. The following sections discuss some of the principal factors.
Rural-to-urban migration
Over the world as a whole, the last century has witnessed substantial rural-to-urban migration.
In the United States and several other countries, a couple of processes have been fundamental
to this shift.
Mechanization of agriculture and farm consolidation
Agriculture was once a largely manual enterprise that required many hands to tend a farm of decent
size.Butwiththeadventoffarmmachinery(tractorsinparticular),thenumberofpeopleneededtodo
farm work was greatly reduced. At the same time, mechanization also encouraged farm consolidation
(in which one farmer buys out another, thereby increasing the acreage owned by the buyer) because
tractors made it possible for a farmer to farm much more land than was the case before. Thus, the
