The Colosseum or Coliseum, also known as the Flavian Amphitheatre or Colosseo, is an oval amphitheatre in the centre of the city of Rome, Italy. Built of travertine limestone, tuff (volcanic rock), and brick-faced concrete, it was the largest amphitheatre ever built at the time. The Colosseum is situated just east of the Roman Forum. Construction began under the emperor Vespasian in AD 72.