Figure 10.15:
Las Vegas, Nevada. Las Vegas is sited in the heart of the desert. As such, its growing demands for water are putting stresses on the natural environment, as water has to be diverted from the Colorado River.
(Robert Cameron/Getty Images.)
Figure 10.13:
Pittsburgh’s Golden Triangle. At the confluence of the Allegheny and Monongahela rivers, Pittsburgh is a classic example of how an early trade-route site has evolved into a commercial center.
(Comstock Select/Corbis.)