The Quirinal Palace (known in Italian as the Palazzo del Quirinale or simply Quirinale) is a historic building in Rome, Italy, one of the three current official residences of the President of the Italian Republic, together with Villa Rosebery in Naples and Tenuta di Castelporziano in Rome. It is located on the Quirinal Hill, the highest of the seven hills of Rome. It has housed thirty Popes, four Kings of Italy and twelve presidents of the Italian Republic. The palace extends for an area of 110,500 square metres and is the ninth-largest palace in the world in terms of area. By way of comparison, the White House in the United States of America is one-twentieth of its size.