Piazza Navona 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, and hence it was known as "Circus Agonalis".
In the 17th century it became a showcase for Baroque design, with work by Bernini and Borromini among others. The Fontana dei Quattro Fiumi stands in front of the Church of Sant’Agnese in Agone.
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Text: introduction of the Wikipedia article Piazza Navona, under the CC BY-SA 4.0 licence (authors: article history). Facts: Wikidata (CC0). Coordinates: Wikidata, map background © OpenStreetMap contributors.