The fountain is at the juncture of three roads (tre vie). It marks the terminal point of the 'modern' Acqua Vergine. One of the ancient aqueducts that supplied water to ancient Rome, stretched 22 km (14 miles) away from the city. This aqueduct (Aqua Virgo) also fed water into the Baths of Agrippa. It served Rome for more than four hundred years.
Numerous alterations were made as the centuries passed.
In 1629 Pope Urban VIII, thought the earlier fountain was losing its beauty and asked Bernini to sketch and give the fountain a new definite, monumental form. When the Pope died the project was shelved!