River Mersey

Mersey, River, major trade waterway rising in the Pennine Hills of northwest England and entering the Irish Sea. About 70 mi (110 km) long, the river has underwater tunnels for railroads and automotive traffic. Its many docks and basins, serving the cities of Liverpool and Birkenhead, have contributed to the development of Birkenhead as an important market for cattle. A canal connects the river to the city of Manchester.