colorado river where does it start and end
Colorado River The Colorado River is one of the principal rivers of the Southwestern United States and northern Mexico (the other being the Rio Grande). The 1,450-mile-long (2,330 km) river drains an expansive, arid watershed that encompasses parts of seven U.S. and two Mexican states. Starting in the central Rocky Mountains in the U.S., the river flows generally southwest across the Colorado Plateau and through the Grand Canyon before reaching Lake Mead on the Arizona–Nevada border, where it turns south toward the international border. After entering Mexico, the Colorado approaches the mostly dry Colorado River Delta at the tip of the Gulf of California between Baja California and Sonora.
Grand Canyon Nearly two billion years of Earth's geological history have been exposed as the Colorado River and its tributaries cut their channels through layer after layer of rock while the Colorado Plateau was uplifted.[4] While some aspects about the history of incision of the canyon are debated by geologists,[5] several recent studies support the hypothesis that the Colorado River established its course through the area about 5 to 6 million years ago.[1][6][7] Since that time, the Colorado River has driven the down-cutting of the tributaries and retreat of the cliffs, simultaneously deepening and widening the canyon.