Missouri is a state in the Midwestern United States. With more than six million residents, it is the 18th-most populous state of the country. The largest urban areas are St. Louis, Kansas City, Springfield and Columbia; the capital is Jefferson City. The state is the 21st-most extensive in area. Missouri is bordered by eight states : Iowa to the north, Illinois, Kentucky and Tennessee to the east, Arkansas to the south and Oklahoma, Kansas and Nebraska to the west. In the south are the Ozarks, a forested highland, providing timber, minerals and recreation. The Missouri River, after which the state is named, flows through the center of the state into the Mississippi River, which makes up Missouri's eastern border.