Carceres
The Roman circus (from Latin, "circle") was a large open-air venue used for public events in the ancient Roman Empire. The circuses were similar to the ancient Greek hippodromes, although circuses served varying purposes and differed in design and construction. Along with theatres and amphitheatres, Circuses were one of the main entertainment sites of the time. Circuses were venues for chariot races, horse races, and performances that commemorated important events of the empire were performed there. For events that involved re-enactments of naval battles, the circus was flooded with water.
According to Edward Gibbon, in Chapter XXXI of his work The History of the Decline and Fall of the Roman Empire, the Roman people, at the start of the 5th century:
...still considered the Circus as their home, their temple, and the seat of the republic.
The performance space of the Roman circus was normally, despite its name, an oblong rectangle of two linear sections of race track, separated by a median strip running along the length of about two thirds the track, joined at one end with a semicircular section and at the other end with an undivided section of track closed (in most cases) by a distinctive starting gate known as the carceres, thereby creating a circuit for the races. The Circus of Maxentius epitomises the design.
The median strip was called the spina and usually featured ornate columns, statues and commemorative obelisks. The turning points on either end of the spina were usually marked by conical poles, called the metae (singular: meta).
The performance surface of the circus was normally surrounded by ascending seating along the length of both straight sides and around the curved end, though there were sometimes interruptions in the seating to provide access to the circus or the seating, or to provide for special viewing platforms for dignitaries and officials. One circus, that at Antinopolis (Egypt), displays a distinct gap of some 50m between the carceres and the start of the ascending seating where there is apparently no structure. This appears to be an exception.
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