Fourth door to the left of the statue of Boris the Bewildered on the fifth floor.
The door requires a password, and can be bolted from the inside. No portrait or statue guards the room's entrance; apparently the door itself recognizes the password. There is one piece of artwork in the bathroom itself, however, a rather flirtatious picture of a mermaid on one wall. Myrtle, who occasionally enjoys spying on the prefects as they bathe, doesn't seem to like her much.

Inside, the bathroom's walls, floor, and single sunken bathtub are all made of white marble, lit softly by a candle-filled chandelier. The rectangular tub is the size and depth of a swimming pool, and even has a diving board, but unlike an ordinary pool the tub is lined with about a hundred taps, each with a differently coloured jewel set into the handle. Each tap automatically releases not only water, but bubble bath (a different kind of bubble bath for each colour-coded handle). A pile of fluffy white towels are kept in one corner.