The total length is about 350 kilometers, the depth is 1,800 meters; the top of the valley is8-25 kilometers wide, the width of the bottom surface line is less than 1 km, and the individual places are only 120 meters. The valley walls on both sides are ladder-like. The climate is dry and the plants are scarce. The valley walls can be observed from the ancient metaozoic to the Cenozoic. The sun is shining, and the deepest part of the canyon ( about 170 km long) is a national park. Located in the middle of the Colorado River in northwest Arizona, southwest of the Colorado Plateau, one of the most magnificent scenery on Earth, some say that the only natural sight visible to the naked eye in space is the Grand Canyon. The Colorado River is the main river in North America. It flows southwest from the Rocky Mountains and into northwest Mexico. It is 2330 kilometers long.