The Map of the USA With Major Rivers Shows that the Country has over 250,000 rivers. Those Rivers provide drinking water, irrigation water, transportation, electrical power, drainage, food, and recreation. According to US Major Rivers Map, The longest river in the USA is the Missouri River; it is a tributary of the Mississippi River and is 2,540 miles long. But the biggest in terms of water volume is the deeper Mississippi River.
The Missouri River is the longest river in the United States at 2,540 miles long. Together with the Mississippi River, it forms the fourth largest river system in the world. The Mississippi River is the 2nd longest river in North America. It has a total length of 2,339 miles (3,765 km) from its source to the sea.
The Colorado River starts from the state of Colorado in the Rocky Mountains and flows down into the Gulf of California. It has a total length of 1,450 miles. The Rio Grande river is one of the longest rivers in the USA. Its mouth is at the Gulf of Mexico and has a length of 1,759 miles.