Which river runs through the Grand Canyon?

The Colorado River runs through the Grand Canyon. It enters the canyon in northern Arizona and cuts through the Colorado Plateau before emerging near Lake Mead.

The river is about 1,450 miles long, beginning in the Rocky Mountains and flowing through Colorado, Utah, and Arizona before reaching Mexico. Its Grand Canyon section is roughly 277 miles long and includes some of North America’s most challenging whitewater rapids.

The canyon was carved over millions of years by erosion, with the Colorado River acting as the primary erosive force. The river also exposed ancient rocks, including formations nearly two billion years old. A common mix-up is confusing the Colorado River with the Little Colorado River, which joins it inside the Grand Canyon but does not run through the canyon’s full length.