Glen Canyon Dam is a concrete arch dam on the Colorado River
in northern Arizona in the United States, near the town of Page.
The dam was built to provide hydroelectricity and flow regulation
from the upper Colorado River Basin to the lower. Its reservoir
is called Lake Powell, and is the second largest artificial lake
in the country, extending upriver well into Utah. The dam is named
for Glen Canyon, a colorful series of gorges, most of which now lies
under the reservoir.