aerial photograph of the River Welland as it flows through Fosdyke Wash salt marsh in Lincolnshire PE12 UK. The River Welland has its source in the Hothorpe Hills, Northahmptonshire, and flows through Market Harborough Corby Stamford and Spalding before exiting into the sea here at Fosdyke Wash. In 1810 engineering works were completed under the supervision of John Grundy Jr to improve the flow of the River and thereby improve drainage of the Deeping Fen. The River has been used for navigation going back to Roman times. Interestingly Fosdyke Wash is 70 miles from Coton in the Elms Derbyshire and the relevance of that is that via that route Coton in the Elms is the furthest point from the sea for any point in Great Britain.