Probably Driftveil, especially in Black/White 2 where it was expanded upon. Also because of Clay, actually the gym is a big part of why I like it because it uses my favorite type of Pokémon.
Opelucid, especially in White and White 2. It had really beautiful music and the atmosphere felt really cool.
I like Village Bridge. I just....love the atmosphere, and the music. So calming. <3 As far as actual cities go, probably Castelia. (and not just because a majority of my stories take place, there! ) Probably just because I like big cities, like that.
Which Route I like the most? Route 1 in Spring! Because of this beautiful pink flowerfields and all these flying petals *____*
My favorite City/Town in Unova will most definitly have to be Humilau city in B2/W2 but i loved the music in Undella town! My favorite route would have to be the route right before Black City/White Forest where you can transfer Pokémon.
Black/Black2's Opelucid and Humilau City. I love the Marine Tube, it's beautiful and I love the music! I like the colourful and modern Opelucid more than the one in White/White2. My favourite route is Route 10. Cool music, free Dusk Stone, and a great spot for EV training.
The music in Driftveil really made me like the place. It was a really cool place in White 2. I went back to Driftveil expecting what the other cities had, which was very little change aside from the gym. But no. Driftveil got a lot bigger between games which which made the place a lot more interesting. I also thought it was cool that the now nice Team Plasma base was there. xD
Castelia for me. Just the way the city did something new with the camera angles and tiling system made it run to run around in circles.
Gosh, there were so many cool cities and places! Village Bridge was awesome with the different instruments and the singer. The Marine Tube was definitely super cool. I think my mouth was hanging open the first time I went through it, haha. Oh, and I loved Virbank City so much with the smooth jazzy music, the fog, and the industrial feel. It just really stood out to me.
My favorite is definitely the Village Bridge. I will periodically go there just to run and surf all over, turn on all the music, and sit and listen to it for a bit. XD;
Fave city? Definitely Ekruteak/Cianwood cities, especially in HG/SS; essentially the same, except now with different touches. Both are just so relaxing! Route: 6/7 in BW, gives me a heroic sense. Entree Forest is also epic; like a Zelda theme with a hint of Final Fantasy. Remember the Silph Co. theme during the Rockets' takeover? Sounded like I was in Dracula's Castle or something.