River Derwent, Yorkshire

The unusual upstream-facing outfall of the Derwent is man-made. It is believed to have been cut during the Roman occupation of Britain to reduce the distance between the Derwent mouth and the Roman legionary headquarters at York by 9 miles. The first navigation weir, also believed to be of Roman origin, was a flash weir built near Wheldrake to raise the level of the river upstream and regulate its flow downstream. It has been suggested that the name "Derwent" is related to that of Deira, one of the post-Roman kingdoms that later became Northumbria. a derivation also found in the Latin name for Malton, . During the reign of King John (1199–1216) a water mill on the Derwent at Wheldrake was…