RAF Wainfleet was a Royal Air Force weapons range on The Wash on the east coast of England near Wainfleet, in the civil parish of Friskney, although the north-east part of the range was in Wainfleet St Mary. Other ranges nearby include RAF Holbeach, also on The Wash, and RAF Donna Nook. It was also known as The Wash Bombing Range. It was only a few miles south-west of Gibraltar Point.

The Wash is a shallow natural rectangular bay and multiple estuary on the east coast of England, United Kingdom. The bay is an inlet of the North Sea. It is the largest estuary system in the United Kingdom, the largest natural bay in England and one of the most important places of conservation in Europe, with several nature reserves.