Detail of a Sea Monster from Bernini's Four Rivers Fountain in Piazza Navona, June 2012

The Fontana dei Quattro Fiumi or "Fountain of the Four Rivers" is a fountain in Rome, Italy, located in the urban square of the Piazza Navona. It was designed in 1651 by Gian Lorenzo Bernini for Pope Innocent X whose family palace, the Palazzo Pamphili, faced onto the piazza as did the church of Sant'Agnese in Agone of which Innocent was the sponsor.

The base of the fountain is a basin from the centre of which travertine rocks rise to support four river gods and above them, an ancient Egyptian obelisk surmounted with the Pamphili family emblem of a dove with an olive twig. Collectively, they represent four major rivers of the four continents through which papal authority had spread: the Nile representing Africa, the Danube representing Europe, the Ganges representing Asia, and the Platte representing the Americas.

Text from: en.wikipedia.org/wiki/Fontana_dei_Quattro_Fiumi