The piazza takes its name from the Quirinal Palace and, like most parts of Rome, is the result of a succession of reconstructions. The fulcrum of the piazza is the Fontana dei Dioscuri, so called because of the two great ancient Roman statues, Castor and Pollux, which embellish the fountain.
They were found in the Baths of Constantine and the basin of the fountain was brought here from the Roman Forum.
The obelisk, which used to decorate Augustus' mausoleum, was only placed here with the fountain at a later date.
Looking onto the piazza are several noteworthy buildings. The most significant, obviously, is the Quirinal Palace itself. Facing this is the Palazzo delle Scuderie, the pope's stables, where his numerous carriages used to be kept. After its restoration by Gae Aulenti, the building is now used as an exhibition center.
On the opposite side of the piazza is the Palazzo della Consulta, built in the 18th century to house the papal Court of the Consulta. Today it is the seat of the Constitutional Court of Italy.
Immediately after this, on the very slope of the hill, is the Palazzo Pallavicini- Pospigliosi, which contains the famous fresco by Guido Reni of the Casino dell' Aurora. This fresco is considered a masterpiece of the classical current present in 17th century painting.