Many people thinks, Tokyo is the city name. Yes, that's right .
Not only a city, but also, Tokyo is a state too.
Now, look at this map. This is only a part of the train map in Tokyo. The green line called Yamanote-line, one of the most famous train in Japan.The city names in the white square, they are all down towns. Each of them is a downtown as big as NYC times square or more than that. When you came to Tokyo! get on Yamanote-line. you can cover modern famous spot easily.