The Tokyo Toilet

It may sound as though I am exaggerating, but no other photographer has used public restrooms in Japan as much as I have.
Daido Moriyama in is introduction to Tokyo Toilet

In a way, public restrooms are an essential but often overlooked prerequisite for street photography. After all, wandering the streets for hours would be unthinkable without them. In his latest photobook Tokyo Toilet, Moriyama having wandered the streets of Tokyo, Osaka, Yokohama and other cities in Japan for decades in search of motifs and moments pays homage to public restrooms in Japans capital. In his unmistakable visual style, he highlights ordinary restrooms in parts of the city he often frequents as well as toilets in buildings designed by famous architects, from Tadao Ando to Shigeru Ban and Takenosuke Sakakura.