Geography Reference
In-Depth Information
Electric trolleys
Around1890,introductionofelectric-poweredtrolleycarsprovidedaquantumleapforwardinspeed.
While a 30-minute walk might allow a commuter to live perhaps as far as 2 miles from work, a com-
mensurate trolley ride could extend the range of residential potential to 5 miles and more. As a result,
the outer edge of urban areas expanded significantly.
Commuter railways
Starting around 1900, commuter railways developed using standard, instead of narrow, gauges. The
result was another quantum leap in speed that expanded the range of commuting to 20 miles and
more. Commuter trains can only travel where tracks are present, of course. Thus, cities expanded
along rail corridors that were rather like tentacles, leaving countryside in between.
Pre-freeway
Advent of mass automobile ownership facilitated unprecedented freedom of choice with respect to
residential location. Suburbs consequently developed and “filled in” substantial portions of rural land
between the commuter rail tentacles described previously. Until roughly the mid-1950s, however,
highways were largely of the 2- and 4-lane variety. Combined with red lights, stop signs, and traffic,
commuting speed was somewhat limited and so too, therefore, the distance at which one may choose
to live from the city.
Freeway
Multi-lane, high-speed, limited access (as in limited points of entrance and exit), divided highways
first appeared in the early 1950s and, in the U.S., proliferated with the advent of the federally funded
Interstate Highway System. Initially, at least, the effect of these arteries was to greatly increase the
average speed at which a motorist could travel and therefore also increase the potential distance from
residence to job. Complemented by construction of
beltways —
interstate-style ring roads designed to
help people travel around the central city without going through it — this ongoing age has witnessed
significant increase in the “filling in” of remaining rural land between commuter rail “tentacles,” and
pushed the outer edge of the city in multiple directions, as shown in Figure 17-3.
