The hamlet Ashton is part of a city located on what river?
Ashton, Cambridgeshire:  It falls within Bainton civil parish, part of the city of Peterborough unitary authority. Peterborough:  Historically part of Northamptonshire, it is 73.6 mi north of London, on the River Nene which flows into the North Sea 30 mi to the north-east.
River Nene