Broad view at sunrise from Mather Point on the South Rim of the Grand Canyon in Grand Canyon National Park. The Grand Canyon is a steep-sided gorge carved by the Colorado River in Arizona. It is one of the first national parks in the United States. The canyon was created by erosion by the Colorado River over a six million year period. The canyon is 277 miles long, ranges in width from 4 to 18 miles, and is over a mile deep (6000 ft.). Nearly 2 billion years of Earth's geological history are exposed, as the Colorado River and its tributaries cut channels through layers of rock while the Colorado Plateau was uplifted. Grand Canyon is a massive rift in the Colorado Plateau that exposes uplifted Proterozoic and Paleozoic strata, and is also one of the six distinct physiographic sections of the Colorado Plateau province. The Grand Canyon is unmatched throughout the world for the vistas it offers to visitors on the rim. The Grand Canyon is known for its overwhelming size and its intricate and colorful landscape. It is geologically significant because of the thick sequence of ancient rocks that are beautifully preserved and exposed in the walls of the canyon. These rock layers record much of the early geologic history of the North American continent.