Trevi Fountain: Overall view of fountain with the facade of Palazzo Poli

Its construction was extremely protracted, but as early as 1735 the architectural framework was complete, and by Salvi's death the ornamental rock formations and full-scale models of most of the sculpture were in place. The fountain is the most monumental water display in Rome and represents the culmination of a tradition of combining water and sculpture within an elaborate architectural setting. Salvi treated an existing fa\u00E7ade of the Palazzo Poli as a nine-bay unit with the central three bays articulated with attached Corinthian columns suggesting an antique triumphal arch. The central bay is treated as a giant niche, which frames Maini's free-standing figure of Oceanus, from which the sculptural scheme and the waters of the fountain seem to flow into a large rock basin. An attic storey above the central niche is surmounted by a coat of arms of Clement XII and incorporates statues representing the Four Seasons, part of a complex iconographic scheme emphasizing the important role of water in nature. Giovanni Battista Maini executed the Oceanus group as drawings and models from 1734. His final full-scale stucco figures, later carved in marble by Pietro Bracci, were placed on the fountain between 1743 and 1759.