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Once Dumbledore's sanctum of secrets, now Snape's prison -- the portraits of former heads still hang on the walls, and Dumbledore's portrait advises from beyond the grave.
The Headmaster's Office under Snape is a room full of ghosts -- not the translucent Hogwarts kind, but the weight of Dumbledore's absence pressing on every surface. Snape takes orders from Dumbledore's portrait, the dead man still pulling strings from a gilt frame. The Pensieve waits in its cabinet -- Harry will use it to view Snape's dying memories and learn the truth about everything. After the battle, Harry enters the office and speaks to Dumbledore's portrait. He explains about the Hallows, the Horcruxes, the walk into the forest. Dumbledore's portrait weeps.
Circular room, spiral staircase, portraits of every Headmaster. Silver instruments, the Pensieve in its cabinet, the Sorting Hat on its shelf. Dumbledore's portrait hangs prominently, eyes twinkling even in paint. Snape sits at the desk he never wanted.
Also known as: Dumbledore's office, the Headmaster's office, Snape's office