The Muskingum River is a tributary of the Ohio River, approximately 111 miles (179 km) long, in southeastern Ohio in the United States. An important commercial route in the 19th century, it flows generally southward through the eastern hill country of Ohio. Via the Ohio, it is part of the Mississippi River watershed. The river is navigable for much of its length through a series of locks and dams.

Ohio is a state in the Midwestern region of the United States. Ohio borders Lake Erie to the north, Pennsylvania to the east, West Virginia to the southeast, Kentucky to the southwest, Indiana to the west, and Michigan to the northwest. Of the 50 U.S. states, it is the 34th-largest by area. With a population of nearly 11.8 million, Ohio is the seventh-most populous and tenth-most densely populated state. Its capital and most populous city is Columbus, with other large population centers including Cleveland, Cincinnati, Dayton, Akron, and Toledo. Ohio is nicknamed the "Buckeye State" after its Ohio buckeye trees, and Ohioans are also known as "Buckeyes". Its flag is the only non-rectangular flag of all U.S. states.