Searching for some London shots, I came across this today. Taken I think for Classic and Sportscar in 1985-6. Little caption info is included with the image, but a quick search leads me to believe it is an Amphicar 770, built between 1961 and 1968. Happy to be corrected!
Taken in Twickenham by one of the ramps adjacent to Eel Pie Island.