This gate, In Kyoto, would be the narrowest gate I have ever seen!
It would be no more than 300mm wide.
Because Japanese houses try to make as much use as possible of very narrow blocks the gate has been put in to provide access to the side of the house.
I wonder how much work you could do down there though. . . . my face would be against the wall as I would only be able to go down it sideways.
For more Unusual House Photos, Wins, and Fails, have a look at: What the………………….?