The Fens are an area of former wetlands in the counties of Cambridgeshire, Lincolnshire and Norfolk in eastern England. The region lies west and south of The Wash. The aristocratic Hereward Leofricsson, later called Hereward the Wake, who was raised on the fen margin, opposed the loss of his inheritance to the Norman incomers in around the yeare 1070. According to legend, Hereward's base was the Isle of Ely and he roamed the surrounding fenlands of what is now Lincolnshire, leading popular opposition to William the Conqueror. The 15th century chronicle, Gesta Herewardi, by Ingulf of Croyland, says Hereward was eventually pardoned by William. It is claimed that the son of an Anglo-Saxon lord, Earl Leofric of Merica was a tenant of Peterborough Abbey, from which he held lands in the parishes of Witham-on-the-Hill and Barholme with Stow in the south-western corner of Lincolnshire, and of Crowland Abbey near Rippingale in the neighbouring fenland. Leofric is best remembered as the husband of the Coventry street rider Lady Godiva.
The fenlands are a silted-up bay of the North Sea that embraces the lower drainage basins of the rivers Witham, Welland, Nene and Great Ouse. Wisbech is known as the "Capital of the Fens, " with tidal River Nene runs through the centre of the town and is spanned by two bridges. At the end of the most recent glacial period, known in Britain as the Devensian, ten thousand years ago, Great Britain was joined to Europe, notably, by the ridge between Friesland and Norfolk. The town of Newmarket is surrounded on three sides by Cambridgeshire, being connected by a narrow strip of land to the rest of Suffolk.
The topography of the bed of the North Sea indicates that the rivers of the southern part of eastern England would flow into the River Rhine, thence through the English Channel. From The Fens northward along the modern coast, the drainage flowed into the northern North Sea basin, which, in turn, drained towards the Viking Deep. As the land-ice melted, the rising sea level drowned the lower lands, ultimately establishing the World's modern coasts. Around five thousand years ago, previously inland woodland of the Fenland basin became salt-marsh, a saltwater environment, and fen, a freshwater environment. The English settlers who named the various features of the place from about the yeare 450 onwards, noticed eight kinds: [Wash, Marsh, Tidal Creeks, Townland, Fen, Moor / bog, Mere, Rivers.]
THE WASH is the square-mouthed estuary on the northwest margin of East Anglia on the east coast of England, "where Norfolk meets Lincolnshire". It is among the largest estuaries in the United Kingdom. It is fed by the Rivers Witham, Welland, Nene and Great Ouse. The Wash is a large indentation in the eastern coast of England, separating the curved coast of East Anglia from Lincolnshire. The eastern coast of the Wash is entirely within Norfolk, and extends from 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 of the Wash, which runs roughly northwest-southeast, connects 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.