If you’re interested in knowing more about the River Thames in England, you might find this link fascinating.
Ron&Lloyd&Less&Pauls Great Adventure
While studying abroad in 1964-5, I and my fellow students decided to explore the river via canoe- from the source to London.
The PowerPoint presentation, created by Les Pitton has been uploaded as HTML.
Lacking GoreTex, Neoprene, Polypro, and real kayaks, we settled for fiberglass covered birch canoes, weighing in a 150 pounds.
By the account of the last lock keeper on the River, the last guy who had done this trip was a US Airman during WWII; but he started in Cricklade, missing the great fun of hauling his canoe over lad about 11 miles.