I'd love to say New York City or London or Berlin (all of which I love), but I think it's Boston (where I live).

Boston is a slower, smaller version of the really amazing big cities, and I think my personality is a smaller version of the personality of a person who thrives in New York, etc. (as a resident, not as a tourist). I'm more laid back and a lot less fond of masses of people than would "work" in a New York City resident.