Omnipresent "KOBAN" - translated as "police detached station"?
If you really have no idea what to do in Japan, you can discover its KOBAN
You have seen them! They are everywhere, omnipresent, nearly invisible and they are among us: the KOBAN.
Koban are small police stations, detached from the main office and in charge of peace within a small territory. Usually, the policemen and women are in the little station, either sitting or standing, but they are also walking or bicycling around, making sure that everything is as it should and that everyone behaves.
But this is Japan, so usually, the few infraction they can verbalise are confined to stopping drivers who have ignored a red light. When they do, they look very enthusiastic doing so... (quite stupid to cross a red light in front of a koban, I agree)
So, Koban has a lot of other missions: like providing assistance to everyone asking for it: explaining the way around, collecting lost-properties are major jobs, making sure that people can cross the road safely is another one.
They are very kind and you should not hesitate to ask them anything.
Koban architecture is simple: a small public space with an old steel desk, 2 pipe chairs, very detailed maps of the area (no google-map) and "wanted" posters on the wall, a blue-uniformed cop (standing or sitting), a bicycle with a huge and white toolbox. Usually, it is 2 story buildings. The major sign to make sure is the green KOBAN sign. But besides that, each Koban is a testimony to the year it was built: old and Japanese traditional, modern, sustainable...
So, if you have no other idea, a walk to discover Koban is one way to discover Tokyo!