The Grand Staircase is a massive structure in Hogwarts Castle, mainly used to access each floor of the castle, including the dungeons. There are hundreds of Portraits covering the walls in this tower, some of which conceal secret passages to other areas within the school. The multiple staircases in the Grand Staircase like to move around, from platform to platform. The stairs go as high as the seventh floor where they come to an end. It was Rowena Ravenclaw who came up with the idea of using moving stairs.
