The Wash

The Wash is the square-mouthed bay and estuary at the north-west corner of East Anglia on the East coast of England, where Norfolk meets Lincolnshire. It is among the largest estuaries in the United Kingdom. The Wash is fed by the rivers Witham, Welland, Nene and Great Ouse.

The Wash is the large indentation in the coastline of Eastern England that separates the curved coast of East Anglia from Lincolnshire. It is a large bay with three roughly straight sides meeting at right angles, each about 15 miles (25 km) in length. The eastern coast of the Wash is entirely within Norfolk, and extends from a point a little north of Hunstanton in the north to the mouth of the River Great Ouse at King's Lynn in the south. The opposing coast, which is roughly parallel to the east coast, runs from Gibraltar Point to the mouth of the River Welland, all within Lincolnshire. The southern coast runs roughly north-west to south-east, connecting these two river mouths and is punctuated by the mouth of a third river, the River Nene.

Inland from the Wash the land is flat, low-lying and often marshy: these are the Fens of Lincolnshire, Cambridgeshire and Norfolk.

Owing to deposits of sediment and land reclamation, the coastline of the Wash has altered markedly within historical times; several towns once on the coast of the Wash (notably King's Lynn) are now some distance inland. Much of the Wash itself is very shallow, with several large sandbanks, such as Breast Sand, Bulldog Sand, Roger Sand and Old South Sand, which are exposed at low tide, especially along the south coast. For this reason, navigation in the Wash can be hazardous. A lightship marks the entrance to the Lynn Channel, the one safe channel from the North Sea to the south coast of the Wash.

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