And this door goes where?

I sore this from the top of the bus on the way home from work the other day and for the life of me I donít know what to make of it.

Yes it is a door with a handle on the outside but with no stairs leading to it or any marks to indicate that there ever was. Looking at the way it is set in to the wall is not a part of the original building and the window has had to be remodelled to fit it.

So where does it go?:confused: