Severn Estuary

The Bristol Channel is a major inlet in the island of Great Britain, separating South Wales from the West Country and extending from the lower estuary of the River Severn (Afon Hafren) to that part of the North Atlantic Ocean known as the Celtic Sea (Môr Celtaidd). It takes its name from the English city of Bristol and is over 30 miles (50 km) across at its widest point.
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For other rivers named "Severn", see Severn River. The River Severn (Welsh: Afon Hafren, Latin: Sabrina) is the longest river in Great Britain, at . It rises at an altitude of on Plynlimon near Llanidloes, in the Cambrian Mountains, Mid Wales, and it passes through a number of English counties, with the county towns of Shrewsbury, Worcester, and Gloucester located on its banks. With an average discharge of 107 m³/s at  Apperley, Gloucestershire, the Severn is England's greatest river in terms of water flow, and is considered one of the ten major rivers of the United Kingdom.
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