Also agree with Hull, Barnsley and Carlisle. Done a bit of work in Hull and the Tesco's was robbed each and every time I was in there, it was just the norm for locals to walk in and take trivial items like chocolate bars and walk out. A lot of poverty around there.
Barnsley as previously mentioned, a lot of travellers and also very dubious family relationships. Even other shitty areas of Yorkshire call them 'backward Barnsley'. I worked with a total nutcase of a bloke from the Cudworth area of Barnsley. That was a fucking sight for sore eyes seeing him try and communicate with some fella from a village near Nottingham. Every other word was 'love' or 'duck', they gave up trying to communicate with each other in the end as they didn't have a clue what each was saying.
Only been to Carlisle on one occasion as a very good friend lived round there for a few years. He's got tales a plenty from round there, very very questionable inbred behaviour. There was certainly an undercurrent in the place when out on the piss, a real nasty little shithole of a place. The villagers on the outskirts of there make Wigan folk look well to do.