What is largest river in the North America?

The Mississippi River is the longest river in North America. It flows for about 3,734 km (2,320 miles) from its source at Lake Itasca in Minnesota to its mouth at the Gulf of Mexico. The Mississippi River Basin drains an area of about 3,200,000 km² (1,230,000 mi²) in the United States and Canada. The Mississippi River is a major transportation route and a source of water for millions of people.