Ohio is a Midwestern state in the northeastern corner of the United States. It was the first and eastern-most state in the Midwest admitted to the Union under the Northwest Ordinance. Its U.S. postal abbreviation is OH; its old-style abbreviation is O. Ohio is an Iroquois word meaning "great water." The name refers to the Ohio River that forms its southern border.
Much of Ohio features glaciated plains, with an exceptionally flat area in the northwest being known as the Great Black Swamp. This glaciated region in the northwest and central state is bordered to the east and southeast first by a belt known as the glaciated Allegheny Plateau, and then by another belt known as the unglaciated Allegheny Plateau.
Ohio is one of the nation's industrial leaders, ranking third in manufacturing employment nationwide. Important manufacturing centers are located in or near Ohio's major cities. Akron is known for rubber; Canton for roller bearings; Cincinnati for jet engines and machine tools; Cleveland for auto assembly, auto parts, and steel; Dayton for office machines.
Attractions include the Rock and Roll Hall of Fame, Indian burial grounds at Mound City Group National Monument, Perry's Victory International Peace Memorial, the Pro Football Hall of Fame at Canton, and the homes of presidents Grant, Taft, Hayes, Harding, and Garfield.