Which river carved the Grand Canyon?

The Colorado River carved the Grand Canyon. Its long history of erosion, combined with uplift of the Colorado Plateau, produced the canyon's immense depth and layered walls.

The river flows through about 277 miles of the Grand Canyon in northern Arizona. Over millions of years, it cut downward through rock while tributaries widened the gorge and weathering caused the cliffs to retreat. The exposed rocks record nearly two billion years of Earth's geological history.

Geologists generally agree that the modern canyon took shape mainly within the last 5 to 6 million years, although the exact sequence of river capture, uplift and erosion remains an active area of research. Cooler, wetter Ice Age conditions increased runoff and strengthened the river's erosive power.

The Grand Canyon is not the work of water alone: wind, landslides, earthquakes and tributary streams also helped shape it. Still, the Colorado River is the defining erosional force and the canonical answer.