Archeology the easy way
Do you remember when I said that the tide rises and falls 30 feet (9m) in London ? The Thames is continually churning the river bed, currents can be flowing one way on the surface, and the opposite on the bottom. The result of this is that objects are always being thrown up and all you need to do is walk along at low tide and you can pick up objects hundreds of years old - quite a few people do, just like here.
The artist Gary Phillips collects these ojects and puts them together into works of art, to quote: "In my work I try to reflect at least 300-700 years of English history". You can see his Last Gasp (what a name!) Gallery here.