Until the end of World War II, this palace was the home of the king of Italy; before the crown resided here, it was the summer residence of the pope. Since 1946 the palace has been the official residence of the President of Italy, but parts of it are open to the public on Sunday mornings.

Few rooms anywhere are as impressive as the richly decorated, 17th-century Salone dei Corazzieri, the Sala d’Ercole (once the apartments of Umberto I but completely rebuilt in 1940), and the tapestry covered 17th-century Sala dello Zodiaco. Despite its Renaissance origins, this palazzo is rich in associations with ancient emperors and deities. The colossal statues of the “Dioscuri,” Castor and Pollux, which now form part of the fountain in the piazza, were found in the nearby Baths of Constantine; in 1793, Pius VI had an ancient Egyptian obelisk moved here from the Mausoleum of Augustus. The sweeping view of the city from the piazza, which crowns the highest of the seven ancient hills of Rome, is itself worth the trip.