The mouth of this river is located between Ballard County, KY and Cairo, IL and has its deepest and widest point located at the city near the McAlpine Locks and Dam. Tributaries of this river include the Wabash, Kentucky, Saline, and Cumberland Rivers. Its source is formed by the confluence of the Allegheny and Monongahela Rivers near Pittsburgh, PA. Other cities located on this river include Louisville and Cincinnati. For 10 points, name this tributary of the Mississippi River, which forms the 
The mouth of this river is located between Ballard County, KY and Cairo, IL and has its deepest and widest point located at the city near the McAlpine Locks and Dam. Tributaries of this river include the Wabash, Kentucky, Saline, and Cumberland Rivers. Its source is formed by the confluence of the Allegheny and Monongahela Rivers near Pittsburgh, PA. Other cities located on this river include Louisville and Cincinnati. For 10 points, name this tributary of the Mississippi River, which forms the southern boundary of the state that has its capital at Columbus.
The mouth of this river is located between Ballard County, KY and Cairo, IL and has its deepest and widest point located at the city near the McAlpine Locks and Dam.
{Ohio} River