If my fellow Americans ever want to be able to distinguish actual UK regional accents, I highly recommend watching “Would I Lie To You?” It really helps to hear so many variations on the same national accent *next* to each other to hear all the regional differences, and that’s a great one for it!
It amuses me that (some) Americans think there's a couple of British accents (Cockney and Received Pronunciation) and everyone lives within 10 miles of London.