I know that talking about manhole covers is not an issue that seems too interesting and that, at first glance, too much of itself. But that's because here our sewer covers are a simple metallic circle, with some type of relief to avoid the risk of skidding and in the best of cases the name of the service company engraved on it, all very gray and unattractive .
In the case of Japan, everything is very different, it is possible that walking through the streets of any Japanese city do not notice them, because everything we have at eye level or looking up, is interesting enough to go looking at the ground, even so sure that at some point we caught the attention of a manhole cover that for its color stand on the asphalt or sidewalk, but here we have an example that certainly does not go unnoticed.
The first time it might seem a curiosity of some street or neighborhood, but little by little we discover that it is not a rarity, but something that extends to all the cities of Japan.
There are all kinds, with designs that make reference to the place, others with geometric designs, in color, without color, etc.
There are annual design competitions for them and each neighborhood or city has a different way when choosing their design for their streets, which become a kind of open-air museum.
In 2016 there was also a company that launched a collection of letters, chips or cards, I do not know how to call them, with about 300 models that are being added every few years, on the front is the photo of the cover with its location while on the back, there is a small explanation of the design or history.