Bicycles

Lots of people in Japan ride bikes around the cities. I didn't see too many of them in Tokyo, but in Kyoto, Hiroshima and Nagoya you see them everywhere.

Unlike at home, your allowed to ride them on the footpath, and on the footpath most streets have a dedicated section for bicycles. 

It also helps that most main roads are really wide (as is the footpath) and the cities are almost completely flat. In Japan all cities seem to be on the plains, the hills and mountains are all covered in trees.