Ohio River

Formed by the confluence of the Allegheny and Monongahela Rivers at Pittsburgh, the Ohio River forms part of the border between Ohio and West Virginia, between Ohio and Kentucky, between Indiana and Kentucky, and between Illinois and Kentucky before joining the Mississippi at Cairo, Illinois.

Since it was considered by pre-Columbian inhabitants of eastern North America to be part of a single river continuing on through the lower Mississippi, it is perhaps an understatement to characterize the Ohio as a mere tributary of the Mississippi. The river is 981 miles (1579 km) long and carries the largest volume of water of any tributary of the Mississippi.

On May 19, 1749 King George II of Great Britain granted the Ohio Company a charter of land around the forks of the Ohio River.

Besides Pittsburgh and Cairo, other cities along the Ohio include:

• Marietta, Steubenville, Portsmouth, and Cincinnati in Ohio
• Wheeling, Parkersburg, and Huntington in West Virginia
• Ashland, Louisville, Henderson, Covington, Owensboro, and Paducah in Kentucky
• Madison, New Albany, Tell City, Evansville, and Mount Vernon in Indiana.