River Severn

The River Severn (Welsh: Afon Hafren, pronounced [ˈavɔn ˈhavrɛn]) is the longest river in Great Britain, with a length of 220 miles (354 km). It is also the river with the most voluminous flow of water by far in all of England and Wales, with an average flow rate of 107 m/s (3,800 cu ft/s) at Apperley, Gloucestershire. It rises in the Cambrian Mountains in mid Wales, at an altitude of 610 m (2,000 ft), on the Plynlimon massif, which lies close to the Ceredigion/Powys border near Llanidloes. The river then flows through Shropshire, Worcestershire and Gloucestershire. The county towns of Shrewsbury, Worcester and Gloucester lie on its course.

The Severn's major tributaries are the Vyrnwy, the Tern, the Teme, the Warwickshire Avon, and the Worcestershire Stour.