The Arithmancy Classroom is where Arithmancy classes are taught at Hogwarts School of Witchcraft and Wizardry. It is located on the seventh floor of Hogwarts Castle. It includes number charts, a blackboard and large rows of tables for students to sit in. It may also be where Advanced Arithmancy Studies is taught.

This wing has hundreds of bookshelves lined along the walls and various tables and furniture placed around the room. It serves the Castle as a reading room and study hall. There are two entrances; one in the seventh floor corridor and the other by the Fat Lady's portrait.

The Ravenclaw Head's office is the thirteenth window from the right of the West Tower. The office contains portraits, a desk, and sleeping quarters.

This is a part of the castle that nearly everyone avoids, for as soon as one steps into the hall, they are hexed with what seems random hexes. There are legends about what lie at the end, but none have made it there, and some have died trying to reach the end. There are wards so ghosts cannot enter the hall at all. Most historians agree that at the end of the hall lies a treasure the four founders found that was decided too powerful for anyone to possess, and created an impenetrable prison for it to be encased in.

Walk past this wall three times, with the wish of what you need the most and a door forms, with what you need inside. The headquarters of the DA can be found here, as well as the prisoner Draco Malfoy.