I
River, North America.
Rising in the Rocky Mountains of Colorado, U.S., it flows west and south 1,450 mi (2,330 km) to empty into the Gulf of California in northwestern Mexico. It drains a vast sector of the North American continent, about 246,000 sq mi (637,000 sq km). No other river in the world has cut so many deep trenches, of which the Grand Canyon is the largest and most spectacular. It is important for hydroelectric power and irrigation; more than 20 dams, including Hoover Dam , have been built on the Colorado River and its tributaries.
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River, south-central Argentina.
Its major headstreams, the Grande and Barrancas rivers, flow southward from the Andes Mountains and meet to form the Colorado near the Chilean border. It flows southeastward across northern Patagonia and the southern
III
River, western Texas, U.S. It flows southeast 862 mi (1,387 km) through prairie, hill, and canyon country past {{link=Austin">Austin and across the coastal plain to enter Matagorda Bay.
The river, the largest entirely within Texas, is the site of flood-control, power, irrigation, and recreational projects.