Piazza Navona is a city square in Rome, Italy. The piazza follows the plan of an ancient Roman circus, the 1st century Stadium of Domitian, where the Romans came to watch the agones ("games"): today's name stems from the corruption of the latter in in agone, then nagone and navona, which actually means "big ship" in Italian.

Defined as a square in the last years of 15th century, when the city market was transferred here from the Campidoglio, Piazza Navona is now the pride of Baroque Rome. It has sculptural and architectural creations: by Gian Lorenzo Bernini, the famous Fontana dei Quattro Fiumi (Fountain of the Four Rivers, 1651) in the center; by Francesco Borromini and Girolamo Rainaldi, the church of Sant'Agnese in Agone; and by Pietro da Cortona, who painted the gallery in the Pamphilj palace.

The market was moved in 1869 to Campo de' Fiori, but the square has also a role in housing theatrical and costume shows, horse races, buffalo jousts. Since 1652, on every August Saturday and Sunday, the square was turned into a lake to celebrate the Pamphilj family. This feast was suppressed in 1866.

Piazza Navona contains two additional fountains sculpted by Giacomo della Porta — the Fontana di Nettuno (1574), located at the northern area of Piazza Navona, and the Fontana del Moro (1576), located at the southern end of the piazza.