I.

Introduction

Ohio (river) (Algonquian for “beautiful river”), river in the east central United States. It flows from Pittsburgh, Pennsylvania, to the Mississippi River at Cairo, Illinois, a distance of 1,580 km (981 mi). The Ohio drains 525,800 sq km (203,000 sq mi) and has an average annual flow of 7960 cu m per second (281,000 cu ft per second), providing slightly less than half of the discharge of the Mississippi River.