Severn River

"The River Severn (Welsh: Afon Hafren, Latin: Sabrina) is the longest river in Great Britain, at about 354 kilometres (220 mi), but the second longest on the British Isles, behind the River Shannon. It rises at an altitude of 610 metres (2,001 ft) on Plynlimon, Ceredigion near Llanidloes, Powys, in the Cambrian Mountains of mid Wales. It then flows through Shropshire, Worcestershire and Gloucestershire, with the county towns of Shrewsbury, Worcester, and Gloucester on its banks. With an average discharge of 107 m³/s at Apperley, Gloucestershire, the Severn is the greatest river in terms of water flow in England and Wales."