The Grand Canyon is a steep-sided canyon carved by the Colorado River in the United States in the state of Arizona. It is contained within and managed by Grand Canyon National Park, the Hualapai Tribal Nation, and the Havasupai Tribe.The Grand Canyon is 446 km long, up to 29 km wide and attains a depth of over a mile .Nearly two billion years of 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. While the specific geologic processes and timing that formed the Grand Canyon are the subject of debate by geologists,recent evidence suggests that 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 its present-day configuration.