Prehistory
In the Pliocene epoch (1.7 million years ago) the River Trent rose in the Welsh hills and flowed almost east from Nottingham through the present Vale of Belvoir to cut a gap through the limestone ridge at Ancaster and thence to the North Sea At the end of the Wolstonian Stage (c. 130,000 years ago) a mass of stagnant ice left in the Vale of Belvoir caused the river to divert north along the old Lincoln river, through the Lincoln gap. In a following glaciation (Devensian, 70,000 BC) the ice held back vast areas of water – called Glacial Lake Humber – in the current lower Trent basin. When this retreated, the Trent adopted its current course into the Humber.
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