Found this on the CR Blog: “Do you speak Pompey?” - a map of Portsmouth with the streets relabelled with examples of apparently local slang. I wouldn’t say very much of this slang is unique to Portsmouth - I hear much of the same phrases and accents in Brighton, and around Sussex and Surrey too - but the map is pretty interesting nonetheless. As CR Blog points out, it’s similar in execution to the NB Studio map of London. It’d be interesting to do a map of a larger region (or country!) showing accents in a similar fashion. It’d be of aesthetic interest more than scientific, but I’d be tempted to buy one.