This crossroads is named after the fountains that decorate its four corners and marks the highest point on Rome's highest hill. The Quirinal Hill was the site of temples, patrician residences and the sumptuous Baths of Constantine in ancient times.

Like the other hills that were abandoned in the Middle Ages, this hill regained its importance only in the 16th century when it was renamed Monte Cavallo after the great equestrian statues of Castor and Pollux. Found in the ruins of the baths, these statues were re-utilized for the fountain in front of the Palazzo Quirinale.
The four fountains at this crossroads were designed by Domenico Fontana for Pope Sixtus V and are a perfect piece of urban planning: they are right at the center of an enchanting triangle created by the obelisks of Santa Maria Maggiore, Piazza del Quirinale and Trinita' de Monti.