Scarborough's sub aqua club is one of the oldest in Britain. They have dived many wrecks on the Yorkshire Coast and have a huge collection of bells and artefacts. In 2015 they put on a display in the Maritime Heritage Centre about UB21 and the many wrecks associated with the German U boat.
See their website http://scarboroughsubaquaclub.net/
One of their members, Carl Racey, created a brilliant website listing thousands of wrecks and the details at: http://www.wrecksite.eu/