Piazza del Campo is the principal public space of the historic center of Siena, Tuscany, Italy and is regarded as one of Europe's greatest medieval squares. It is renowned worldwide for its beauty and architectural integrity. The Palazzo Pubblico and its Torre del Mangia, as well as various palazzi signorili surround the shell-shaped piazza. At the northwest edge is the Fonte Gaia.
The twice-a-year horse-race, Palio di Siena, is held around the edges of the piazza.
The open site was a marketplace established before the thirteenth century on a sloping site near the meeting point of the three hillside communities that coalesced to form Siena: the Castellare, the San Martino and the Camollia. Siena may have had earlier Etruscan settlements, but it was not a considerable Roman settlement, and the campo does not lie on the site of a Roman forum, as is sometimes suggested. It was paved in 1349 in fishbone-patterned red brick with ten lines of travertine, which divide the piazza into nine sections, radiating from the mouth of the gavinone (the central water drain) in front of the Palazzo Pubblico. The number of divisions are held to be symbolic of the rule of The Nine (Noveschi) who laid out the campo and governed Siena at the height of its mediaeval splendour between 1292-1355. It was and remains the focal point of public life in the City. From the piazza, eleven narrow shaded streets radiate into the city.