Natural amphitheatre

An amphitheatre or amphitheater /ˈæmfɪˌθiːətər/ is an open-air venue used for entertainment, performances, and sports. The term derives from the ancient Greek ἀμφιθέατρον (amphitheatron), from ἀμφί (amphi), meaning "on both sides" or "around" and θέατρον (théātron), meaning "place for viewing".

Ancient Roman amphitheatres were oval or circular in plan, with seating tiers that surrounded the central performance area, like a modern open-air stadium. In contrast both ancient Greek and ancient Roman theatres were built in a semicircle, with tiered seating rising on one side of the performance area. In modern usage, an "amphitheatre" is theatre-style stages with spectator seating on only one side, theatres in the round, and stadia. Natural formations of similar shape are sometimes known as natural amphitheatres.

Ancient Roman amphitheatres were major public venues, circular or oval in plan, with perimeter seating tiers. They were used for events such as gladiator combats, chariot races, venationes (animal hunts) and executions. About 230 Roman amphitheatres have been found across the area of the Roman Empire. Their typical shape, functions and name distinguish them from Roman theatres, which are more or less semicircular in shape; from the circuses (similar to hippodromes) whose much longer circuits were designed mainly for horse or chariot racing events; and from the smaller stadia, which were primarily designed for athletics and footraces.

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