An early version of Splatoon was designed to allow travel via urinals.
It's unclear at what point the toilet-based transportation was taken out of Nintendo's paint-based shooter - or if it ever made it into a playable build.
But official concept art for the feature has cropped up, courtesy of a new Japanese artbook (thanks, Destructoid).
Splatoon's final version allows you to warp around a map instantly by tapping on one of your teammates via the GamePad's map.
It's likely that Nintendo chose this method of travelling was more useful than a version based around the map's plumbing - although perhaps then Mario could have put in an appearance?