Model of the Stadium of Domitian | Flickr: Gary Todd CC-BY 2.0Antiquity
Already in 46 BC, Caesar had a sports field for athletic competitions built on the current site, which was expanded in 85 BCE by Emperor Domitian and offered space for over 30,000 visitors. The stadium was used for horse races, gladiator games, and athletics competitions.
The name of the square probably derives from the Latin word agones and means 'competition' or 'games'. The name of the square then developed from agone to nnagone, to navone, and finally Navona.
Piazza Navona 1699 | Wiki Commons: By Gaspar van Wittel - Colección Carmen Thyssen-Bornemisza en depósito en el Museo Thyssen-Bornemisza, Public Domain, https://commons.wikimedia.org/w/index.php?curid=7699036The Middle Ages
Wealthy Romans moved to the city and started to frame the square with buildings. A first church was also built. In this church, the Sant'Agnese in Agone, you can visit the remnants of the ancient stadium today. Nonetheless, horse races, fairs, markets, and festivals still took place in the square.
The shape of the arena remains preserved to this day, as the builders used the outer walls for their houses.The Baroque Era
The square was to be rebuilt as the Forum Pamphilj following the model of pompous imperial forums. This was the reason why an ancient aqueduct was extended to this point. However, the Forum remained unfinished. Thanks to the aqueduct, the Neptune Fountain, the Fontana del Moro, and the Fountain of the Four Rivers are now standing here. The four rivers symbolize the largest rivers of the previously known four continents: the Danube, the Nile, the Ganges, and the Rio de la Plata.The Cool Waters
The summers of the Eternal City could get very hot, which is why starting from the 17th century, Romans regularly flooded the square by blocking the fountain drains to create a kind of open-air swimming pool for cooling off. However, due to the rapid spread of malaria and concerns about an epidemic in Rome, this water fun was prohibited in the mid-19th century.