Location from harry-potter-prisoner-of-azkaban by
The Gryffindor common room and dormitories, guarded first by the Fat Lady and then by Sir Cadogan after Sirius Black slashes her portrait trying to get inside.
Gryffindor Tower is where courage goes to slouch in armchairs and avoid homework. This year the common room carries extra tension — Sirius Black attacked the portrait guarding the entrance, and Sir Cadogan's erratic password changes (Neville wrote them all down and lost the list, giving Black access) have made security a running source of anxiety. The room still smells of wood smoke, butterbeer smuggled from Hogsmeade, and whatever Neville's latest Herbology project is emitting. Hermione has claimed the best table by the window for studying, Ron and Harry play chess by the fire, and the twins test products on first-years in the corner. The Fat Lady eventually returns, shaken but restored, and demands six security trolls before she'll resume her duties.
A round, cozy tower room hung with scarlet tapestries and furnished with squashy armchairs in crimson and gold. A large fireplace dominates one wall, always crackling. The entrance was guarded by the Fat Lady's portrait until Sirius Black slashed it with a knife; Sir Cadogan replaced her — a small, combative knight who changes the password twice a day and challenges everyone to duels. Spiral staircases lead up to the dormitories.
Also known as: Gryffindor Tower, the Gryffindor common room, Gryffindor common room