This delightful room, originally used for parties, balls and academic events, still has all the original, highly refined plaster decorations designed around 1764 by the architect E.A. Petitot and made by the plasterer Benigno Bossi. The decorations over the doors at the upper ends of the short side are extremely impressive, with symbols of music, the theater, the arts and geometry, and the four pairs of cherubs that, at the corners between the walls and the ceiling, bear boughs of oak, alluding to royal power, and shields with Mercury's helmet, symbolizing in turn a reference to the prudence, diligence and glory of royal power. On the inside are precious testimonies to the brief, tumultuous period in which Maria Luigia of Hapsburg was the bride of Napoleon Bonaparte and Empress of the French.