I can't speak for everywhere in Japan, but in the places I have lived, the city always has cute man hole covers. In Kitakami, where I used to live, they had the onikenbai dancers on the cover. Where I live now is famous for it's rose garden and so the covers have roses on them.
We took out some paper and crayons and did some rubbings on the covers.
Then when we got home we painted them with water colours.
Our paper wasn't big enough to get the whole of this cover, there should be a fireman with the firefighter.
Do you have fancy manhole covers? What do you have on them?