The Quirinal Hill is today identified with the Palazzo del Quirinale, the official residence of the President of the Italian Republic and one of the symbols of the State. Before the abolition of the Italian monarchy in 1946, it was the residence of the king of Italy, and before 1871 it was, as originally, the residence of the Pope.The healthy cool air of the Quirinal attracted aristocrats and papal families that built villas where the gardens of Sallust had been in antiquity. A visit to the villa of Cardinal Luigi d'Este in 1573 convinced Pope Gregory XIII to start the building of a summer residence the following year, in an area considered healthier than the Vatican Hill or Lateran: his architects were Flaminio Ponzioand Ottaviano Nonni, called Mascherino; under Pope Sixtus V works were continued by Domenico Fontana (the main facade on the Piazza) and Carlo Maderno, and by Gian Lorenzo Bernini for Pope Clement XII. Gardens were conceived by Maderno. In the 18th century, Ferdinando Fuga built the long wing called the Manica Lunga, which stretched 360 meters along via del Quirinale. In front lies the sloping Piazza del Quirinale where the pair of gigantic Roman marble Horse Tamers representing Castor and Pollux, found in the Baths of Constantine, were re-erected in . In Piranesi's view the vast open space is unpaved. The Palazzo del Quirinalewas the residence of the popes until 1870, though Napoleon deported both Pius VI and Pius VII to France, and declared the Quirinale an imperial palace. When Rome was united to the Kingdom of Italy, the Quirinale became the residence of the kings until 1946.