The Fountain of Neptune is located in Piazza Navona in Rome. Immediately after the restoration of the Aqua Virgo aqueduct, in 1570, were designed a number of fountains. Among the first commissioned by Pope Gregory XIII in 1574 to Giacomo della Porta, there are the two located at each end of Piazza Navona. The project included a bathtub-shaped marble resting on two mixed-line steps. The subsequent improvements made by Bernini in 1651 concerned the removal of the railings and steps and a wider pool around the fountain, which contained the previous one, with the same design mixtilinear. The fountain took its present name following the addition of two sculptural groups, 'The Neredei with cherubs and sea horses' by Gregorio Zappalà and 'Neptune's fight against an octopus' of Antonio della Bitta, which took place following a public competition announced by the City of Rome in 1873 to create a stylistic consonance with these other two fountains at Piazza Navona.