risk steves once showed a beach in london near thames river i think near the eye where he would go to discover trinkets like ceramic pieces from roofs and cigarettes etc where was that again ?
It's called mudlarking. The best spots are further downstream on the left bank right about even with St Pauls. It's tricky. You need a permit to dig or even lift a rock or anything else. There are restrictions on what you can keep. Tide knowledge is really important. Study up on it before you try it.
I don't think I would call it beach. Just the river banks of the Thames river at low tide. Just walk along the Thames river and look for breaks with stairs leading down to the river bank.
You can't just walk down there, it takes basic equipment (such as old clothes and boots - - hence the name mudlarking).
London Walks actually does some mudlarking walks. Here's the info if you are interested. http://www.walks.com/London_Walks_Home/Thames_Beachcombing_/default.aspx