Which is the best American city you've ever been to? Why?

Hi from England, I loved Flagstaff, Arizona. Everyone was friendly and didnt seem in a rush like the rest of the USA. I really liked it one Saturday night when i found an plaza where the town council had put on a film projected onto the side of a building and everyone was sat around eating hotdogs and popcorn. The kids loved it as it was Brother Bear. I also liked Waikiki on Oahu because basically it was NUTS and never went to sleep and brides and grooms were walking in and out of cafes and bars still wearing their wedding outfits.