The Grand Canyon is 446 km
long, up to 29 km wide and attains a depth of over 1,800 meters.
Nearly two billion years of
the Earth's geological history have been exposed as the Colorado River and its
tributaries cut their channels through layer after layer of rock while the
Colorado Plateau was uplifted by tectonic action.
Evidence suggests the
Colorado River established its course through the canyon at least 17 million
years ago. Since that time, the Colorado River continued to erode and form the
canyon to the point we see it at today.