The fountain was created by the sculptor Leonardo Sormani (documented between 1530 and 1589) based on a 1575 design by the architect Giacomo della Porta (1533-1602).
The fountain consisted of a quadrangular basin in grey African marble with the sides interrupted by four circular arcs, surmounted by a baluster supporting a basin.
Author: Giacomo della Porta; Leonardo Sormani; Filippo Barigioni; Luigi Amici.
Date: 1575; 1662; 1711; 1880; 1928.
Materials: antique grey marble, travertine, Carrara marble, Proconnesian marble, red granite, bronze
Original power supply: Vergine aqueduct
Four masks were inserted into the handles of the semicircles, on the back of which were depicted as many dragons, heraldic symbols of Pope Gregory XIII Boncompagni (1572-1585). An external balustrade and three steps surrounded the basin.
Today, only the basin remains of the original complex. In 1662, the level of the square was lowered, the balustrade and the Dellaportian steps were removed and the current large base was created, which repeats the mixtilinear motif of the basin.
In 1711, by order of Pope Clement XI Albani (1700-1721), the central obelisk supported by a complex sculptural base, the work of Filippo Barigioni (ca. 1690-1753), was added in place of the upper basin. The obelisk of Ramses II rises on a fake travertine cliff, on which a plinth decorated with dolphins at the corners is grafted, while on two faces of the same plinth two monumental Albani coats of arms are sculpted. On the other faces an epigraph celebrating the interventions of Clement XI is repeated. At the base of the plinth there are inscriptions relating to the restorations.