Grand Canyon viewed from Hopi Point, on the south rim. New evidence suggests the western Grand Canyon was cut to within 70 percent of its current depth long before the Colorado River existed.
The Grand Canyon is indeed a very big hole in the ground. It is 277 miles (446 km) long, up to 18 miles (29 km) wide and more than a mile (6,000 feet / 1,800 meters) deep. It is the result of constant erosion by the Colorado River over millions of years.
Where is the Grand Canyon?
The Grand Canyon is in the northwest corner of Arizona, close to the borders of Utah and Nevada. Most of the Grand Canyon lies within Grand Canyon National Park and is managed by the National Park Service, the Hualapai Tribal Nation and the Havasupai Tribe.
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