This famous steep-sided canyon carved by the Colorado River in Arizona, USA is the Grand Canyon. The Grand Canyon is known for its visually huge size and its detailed and colorful landscape. The rock layers found here record a lot of the early geologic history of the North American continent. This is a natural wonder that you almost have to see to believe it. The deepest part of the canyon is over a mile in depth. Most wildlife in this area are rodents and bats surprisingly. Rafting, hiking, running, and helicopter tours are popular activities to do at the Grand Canyon.