Location from harry-potter-prisoner-of-azkaban by
A derelict house on the outskirts of Hogsmeade, built to contain Remus Lupin's werewolf transformations and now the site where the truth about Sirius Black, Peter Pettigrew, and the Potters' betrayal finally comes to light.
The Shrieking Shack is where Prisoner of Azkaban's truth detonates. A massive black dog drags Ron through the Whomping Willow tunnel by his broken leg, and Harry and Hermione follow into the most haunted building in Britain — which was never haunted at all, only inhabited by a teenage werewolf once a month. Inside, Sirius Black stands over Ron, skeletal and wild-eyed. Lupin arrives and embraces him — they haven't seen each other in twelve years. Snape appears with his wand drawn, old hatred burning. And then the truth: Pettigrew is alive, hiding as Scabbers, the real traitor who betrayed the Potters. The confrontation is raw — Sirius shaking with rage, Lupin logical and precise, Pettigrew groveling, Harry standing between them making the choice to spare Pettigrew's life. Then the full moon rises through the boarded windows, Lupin transforms, Pettigrew escapes, and everything falls apart.
A decrepit wooden house with boarded windows, a sagging roof, and an overgrown yard. The interior is wrecked — furniture smashed, wallpaper shredded, deep claw marks gouged into every surface from years of Lupin's transformations. A tunnel from the Whomping Willow connects to the basement. Dust covers everything. The floorboards creak ominously.
Also known as: the Shrieking Shack, Shrieking Shack, the most haunted building in Britain