That's the case with all the urban centres. Sheffield and Barnsley are totally, totally different even though they are only 8 miles apart, and as a Leeds resident I can distinguish between different sides of the city. You do have to be a local to hear it though, and if you aren't exposed to it constantly you lose the familiarity. Some years ago, when I'd spent a lot of time in Leeds and not much elsewhere, I managed to amaze a group of people in a hotel on the south coast. They were there on business. I was at the next table and I could overhear them. I commented that their Yorkshire accents made me feel at home. "Oh really, where are you from?"
"Leeds"
"Oh really, me too"
"Yes, I can hear that. Your colleagues aren't though. One's from further west, I think Bradford, Halifax, that way on, the other further east, towards York, Selby sort of area."
Cue a short silence, and then "Er, yes, I'm from near Halifax as it happens, and so-and-so here...Doncaster."