It's not really a manhole cover, but Sendai also has decorative access panels for their underground utilities.

Here's another manhole cover, this time from Yuzawa. You can see Inukko Matsuri represented by the dog and shrine in the lower right corner.

In America, manhole covers are a largely ignored part of the urban landscape. They are quite plain, bearing little more than a note of what utility it serves and a tread pattern so that pedestrians won't slip.

In Japan, though, each municipality has manhole cover designs that reflect local specialties, historical sites, or festivals. Whatever a town is famous for may end up on the manhole covers.

Here's one of Kitakami's designs:



And one from Hottoyuda, famous for its hot springs:



And one from Yokote, depicting Yokote Castle, a kamakura (snow hut), and cherry blossoms: