Beginning in western Pennsylvania at the confluence of the Allegheny River and Monongahela River in Pittsburgh, the Ohio River helps form parts of the borders of Ohio, Kentucky, Indiana and Illinois, although no part of the river actually belongs to Illinois. Its northern banks are actually a part of Kentucky's northern state line. It flows by several major cities including Wheeling, WV, Cincinnati, OH, Louisville and Paducah, KY and Evansville, IN.
The river passes by the Ohio cities of Marietta, South Point, Ironton, Portsmouth, New Richmond, Newtown, Cincinnati, and North Bend. It empties into the Mississippi River in southern Illinois near Cairo.