the Ohio River
/ði əʊˌhaɪəʊ ˈrɪvə(r)/
/ði əʊˌhaɪəʊ ˈrɪvər/
- a major river in the eastern central US. It begins at Pittsburgh, Pennsylvania, where the Allegheny River and Monongahela River come together, and flows 981 miles/1 578 kilometres past Cincinnati and into the Mississippi River at Cairo, Illinois. The Ohio was the main route to the West in the late 18th and early 19th centuries.