The River Wissey is a river in Norfolk, eastern England. It rises near Bradenham, and flows for nearly 31 miles (50 km) to join the River Great Ouse at Fordham. The lower 11.2 miles (18.0 km) are navigable. The upper reaches are notable for a number of buildings of historic interest, which are close to the banks. The river passes through the parkland of the Arts and Crafts Pickenham Hall, and further downstream, flows through the Army's Stanford Training Area (STANTA), which was created in 1942 by evacuating six villages. The water provided power for at least two mills, at Hilborough and Northwold. At Whittington, the river becomes navigable, and is surrounded by fenland. A number of pumping stations pump water from drainage ditches into the higher river channel.

The River Great Ouse is a river in England, the longest of several British rivers called "Ouse". From Syresham in Northamptonshire, the Great Ouse flows through Buckinghamshire, Bedfordshire, Cambridgeshire and Norfolk to drain into the Wash and the North Sea near Kings Lynn. Authorities disagree both on the river's source and its length with one quoting 160 mi (260 km) and another 143 mi (230 km). Mostly flowing north and east, it is the fifth longest river in the United Kingdom. The Great Ouse has been historically important for commercial navigation, and for draining the low-lying region through which it flows; its best-known tributary is the Cam, which runs through Cambridge. Its lower course passes through drained wetlands and fens and has been extensively modified, or channelised, to relieve flooding and provide a better route for barge traffic. The unmodified river would have changed course regularly after floods.