The Grand Canyon is a steep-sided canyon carved by the Colorado River in Arizona, United States. The Grand Canyon is 277 miles long, up to 18 miles wide and attains a depth of over a mile. The canyon and adjacent rim are contained within Grand Canyon National Park, the Kaibab National Forest, Grand Canyon–Parashant National Monument, the Hualapai I…The Grand Canyon is a steep-sided canyon carved by the Colorado River in Arizona, United States. The Grand Canyon is 277 miles long, up to 18 miles wide and attains a depth of over a mile. The canyon and adjacent rim are contained within Grand Canyon National Park, the Kaibab National Forest, Grand Canyon–Parashant National Monument, the Hualapai Indian Reservation, the Havasupai Indian Reservation and the Navajo Nation. The surrounding area is contained within the Baaj Nwaavjo I'tah Kukveni – Ancestral Footprints of the Grand Canyon National Monument. President Theodore Roosevelt was a major proponent of the preservation of the Grand Canyon area and visited it on numerous occasions to hunt and enjoy the scenery.