In a typical section of the canyon, separate rock layers can be seen piled vertically like a stack of pancakes. At the bottom of the canyon are the most ancient rocks of all, Precambrian schists and gneisses, from half a billion to a billion years old. Beginning about 1850, a series of expeditions commanded by officers of the United States Army surveyed the canyon and the surrounding area. The construction of the Glen Canyon Dam in Arizona in 1963 dramatically reduced the natural flow of sand and nutrients down the Colorado River and into the Grand Canyon. Grand Canyon National Park Grand Canyon National Park, in northern Arizona, established as a national monument in 1908 and as a national park in 1919.
Paved roads wind around the Grand Canyon's rims, and trails descend into the canyon.
The extreme variations in elevation from the depths of the canyon to the northern rim have produced four distinct zones of climate and plant life. I've been trying to track down any later info, but haven't had much luck. Interestingly, the area below the North Rim has many Egyptian names. Around Ninety-four Mile Creek and Trinity Creek are geologic formations with names like Tower of Set, Tower of Ra, Horus Temple, Osiris Temple, and Isis Temple. In the Haunted Canyon area are Cheops Pyramid , the Buddha Cloister, Buddha Temple, Manu Temple and Shiva Temple.