I've been to and really liked a lot of Cities like Barcelona, Hong Kong, Singapore, Bangkok, Boston, Melbourne, Quebec, Montreal, Victoria and quite a few I didn't think were all that special, like Miami, Athens, but by far the one I was most impressed with was Tokyo.
First time we went a friend told us where to visit as we had 6 days there. So we had this list. Everywhere is reachable by train/underground, all trains are dead clean and bang on time. I get the feeling passengers would clean any marks or dirt if reqd.
So you go to an area of the city like Ginza or Ueno, you walk out of the station and every area is completely different and like a city in it's own right. One will have ancient temples, one will have a thousand market stalls, one is a city of the future, one is shopping malls, Ueno is full of big beautiful parks, Shinjuku is brighter than Vegas at night.
Everything is open late, very clean and the people are very friendly with a good sense of humour and helpful and seem to love visitors.
Hardly any crime. I think everyone is very proud of whatever job they do and do it to the best of their ability. (which I admire). I'd rate Japanese as the best dressed race on earth, they love nice clothes.
Eg taxi drivers outside stations, they wear suits, sometimes white gloves and have the cleanest taxi's I've ever been in. Seats have starched white covers. Also they won't give you fake notes in your change like they do in China.
Have been a few times now and can't wait to go again to the north of the country.
It's like 6 cities in one. here is a map of Tokyo underground :) You can get bullet trains to other cities. All ticket machines are multi-lingual so you just press the English button and hey presto!
Most people hardly ever drive.
Cleanliness is very impressive...