Piazza Navona (pronounced [ˈpjattsa naˈvoːna]) is a public open space in Rome, Italy. It is built on the site of the 1st century AD Stadium of Domitian and follows the form of the open space of the stadium in an elongated oval. The ancient Romans went there to watch the agones ("games"), and hence it was known as "Circus Agonalis" ("competition arena"). It is believed that over time the name changed to in avone to navone and eventually to navona. In the 17th century it became a showcase for Baroque design, with work by Bernini and Borromini among others.
https://en.wikipedia.org/wiki/Piazza_Navona