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 serving varying purposes. 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.