On this side of the Atlantic …
I-95 in NJ / PA, it’s the most confusing highway I have ever known. You head south from the GWB in NJ and it splits into a western spur and an eastern spur, if you don’t know for sure what exit you want you can be in real trouble, it merges once more just north of Newark airport, but wait 
At exit 7A southbound the signs do not say I-95 anymore, they say ‘NJTPK’, you go over the Delaware Memorial bridge and it then becomes I-95 again. Coming north in Delaware it’s I-95, you stay on I-95 and it doesn’t take you over the bridge, it goes up the western side of the Delaware river and you end up in Philadelphia, nowhere near the NJ turnpike. I -95 ends just north of Trenton NJ, you then head south on I-295 to I-195 eastbound which then meets I-95 in NJ at exit 7A 
As for cities… Trenton, Philadelphia, NYC, Detroit and Chicago are all hell to drive through.