[kyashan]

N.Italians are still S.European looking, although they are generally fairer in pigmentation and different in look compared to S.Italians.
Besides that, there are many other differences regarding genetics, culture, linguistics, gastronomy and so forth.
Sicilians and Piedmonteses can't understand each other speaking in their native tongue, simply beacause they don't belong to the same ethnicity. Someone could say that ethnicity is an arbitrary thing, but for sure they are more different than let's say, catalans are to spanish or a occitans are to normans or serbians are to croatians.