Mississippi River: North America’s Mighty River

The Mississippi River is the second longest river in North America (after the Missouri River) and the fourth longest river in the world (after the Nile, Amazon and Yangtze rivers).The Missouri and Ohio rivers merge with the Mississippi River just north of St. Louis, Missouri, and at Cairo, Illinois, respectively.Although these are major rivers themselves, the Missouri River and the Ohio River are considered tributaries of the Mississippi River.