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The Colosseum, originally called the Flavian Amphitheatre, is an elliptical ampitheatre in Rome. It is the largest ever built in the Roman Empire and quite rightly known as the greatest example of Roman architecture and engineering. Occupying a site just east of the Roman Forum, construction started between AD 70 and 72 during the period of Vespasian and was completed in 80 AD in the reign of Titus