Grand Canyon National Park is a steep sided canyon carved by the Colorado River in the state of Arizona, USA. It is 277 miles long, up to 18 miles wide and attains a depth of over a mile. A UNESCO World Heritage Site since Photo: Baul de Fotos
Carved out by the Colorado River, the canyon is 277 miles long, up to one mile deep and up to 15 miles wide. Millions of years of exposure has formed colorful layers of the Colorado Plateau in mesas and canyon walls.