Geography Reference
In-Depth Information
Finding Sites for Cities
While the civilizations that produced those early cities are things of the past, the locations
of urban hearth areas demonstrate a geographic principle that has persisted through time.
Namely, cities don't just happen. Instead they tend to spring up in particular locations because
of some characteristic(s) of place that was attractive to settlers.
For example, and strange as it may seem today, the Spaniards settled the Los Angeles, California area
for its agricultural potential. Mountains and foothills come down to the sea along the West Coast, af-
fording limited venues for agriculture and settlement. Los Angeles area, however, offered a substan-
tial expanse of relatively flat land complemented by a then-adequate local water supply that trickled
down from the fringing San Gabriel Mountains. That was then. Today, few, if any, people live in LA
because of its crops potential (legal ones, that is), and that makes an important point about urban loc-
ation factors. Namely, the reason why a city began at a particular location may have nothing to do
with the reasons why people live there today.
The list of factors that explain why cities began and developed at particular sites is lengthy. The four
that are discussed in the following sections are the most popular.
Confluence
A
confluence
is a place where two rivers meet to form a combined flow. Pittsburgh, Pennsylvania, for
example, began as a small settlement where the Allegheny and Monongahela Rivers join to form the
Ohio River. Other examples are St. Louis, Missouri, near the point where the Missouri and Missis-
sippi join waters; Khartoum, Sudan, where the White Nile and Blue Nile come together; and Manaus,
Brazil, where the Amazon and Rio Negro combine their waters.
Rivers served as highways in olden times, so being at a confluence was like being at the hub of a
transportation network. Confluences are prone to flooding, however, so availability of high ground is
essential for safe settlement. Fortunately, plenty of high ground is available in Pittsburgh. In contrast,
the land is rather low-lying where the Mississippi and Missouri meet. For that reason, St. Louis is not
located right at that confluence, but a few miles downriver, where the banks are appreciably higher.
