The fountain at the junction of three roads (tre vie) marks the terminal poin of the "modern" Acqua Vergine, the revived Aqua Virgo, one of the aqueducts that supplied water to ancient Rome. In 19 BC, supposedly with the help of a virgin, Roman technicians located a source of pure water some 13 km (8.1 mi) from the city. (This scene is presented on the present fountain's façade.) However, the eventual indirect route of the aqueduct made its length some 22 km (14 mi). This Aqua Virgo led the water into the Baths of Agrippa. It served Rome for more than 400 years.
Legend holds that in 19 BC thirsty Roman soldiers were guided by a young girl to a source of pure water thirteen kilometres (8.1 miles) from the city of Rome. The discovery of the source led Augustus to commission the construction of a twenty-two-kilometre (14-mile) aqueduct leading into the city, which was named Aqua Virgo, or Virgin Waters, in honour of the legendary young girl. The aqueduct served the hot Baths of Agrippa, and Rome, for over four hundred years.
In 1629 Pope Urban VIII, finding the earlier fountain insufficiently dramatic, asked Gian Lorenzo Bernini to sketch possible renovations, but the project was abandoned when the pope died. Though Bernini's project was never constructed, there are many Bernini touches in the fountain as it exists today. An early, influential model by Pietro da Cortona, preserved in the Albertina, Vienna, also exists, as do various early 18th century sketches, most unsigned, as well as a project attributed to Nicola Michetti one attributed to Ferdinando Fuga and a French design by Edme Bouchardon.
Competitions had become the rage during the Baroque era to design buildings, fountains and even the Spanish Steps. In 1730 Pope Clement XII organized a contest in which Nicola Salvi initially lost to Alessandro Galilei – but due to the outcry in Rome over the fact that a Florentine won, Salvi was awarded the commission anyway. Work began in 1732 and the fountain was completed in 1762, long after Salvi's death, when Pietro Bracci's Oceanus (god of all water) was set in the central niche.
Salvi died in 1751 with his work half finished, but he had made sure a stubborn barber's unsightly sign would not spoil the ensemble, hiding it behind a sculpted vase, called by Romans the asso di coppe, the "Ace of Cups".
The Trevi Fountain was finished in 1762 by Giuseppe Pannini, who substituted the present allegories for planned sculptures of Agrippa and "Trivia", the Roman virgin. It was officially opened and inaugurated on May 22 by Pope Clemens XIII It remains one of the most historical cultural landmarks in Rome.
The majority of the piece is made from Travertine stone, quarried near Tivoli, about 35 kilometres (22 miles) east of Rome.
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