both as a resident and traveler leads me to think that it's very different in this regard. Sure other places that I've lived (NYC, DC, SF, Budapest, Vienna) all have their unique neighborhoods - but London has 2,000 years of history living beneath each of the neighborhoods and the way that they have organically grown from a few dozen towns, villages and hamlets into being this one 21st behemoth gives it, IMO, a different character. Clapham and Camden Town, Kensington and Southwark each have an originality and a richness that I don't see quite as strikingly in other cities.