The Tioga River (/ˈtaɪoʊɡə/ TIE-o-guh) is a tributary of the Chemung River, approximately 58 miles (93 km) long, in northern Pennsylvania and western New York in the United States. It drains a region of ridges in the northern Allegheny Plateau in the watershed of the Susquehanna River. In the 19th century, trees logged in the Tioga Valley were extensively used in shipbuilding. Logs were floated down the Tioga and the Chemung to the Susquehanna River and on to the Chesapeake Bay and the shipyards of Baltimore.