OK, this door isn't very exciting to look at. But it's the door to the Sleeping Chamber in the Courtyard of the Black Eunuchs.
It's in the Topkapi Palace, Istanbul.
The room itself is a bit poky even though several people used it. I don't think being a black eunuch in the Ottoman Court was a very good job, frankly. Not only did they chop off your penis and testicles and force you into a life of castrated slavery, but you had to share a room.