Colosseum

Begun by Vespasian around AD 72 and inaugurated by his son Titus in AD 80, the Flavian Amphitheatre held up to 50,000 spectators who watched gladiatorial combat, animal hunts, and public executions. Titus's opening games ran 100 days and reportedly slaughtered 9,000 beasts. A complex of trapdoors and lifts beneath the arena floor, the hypogeum, hoisted animals and scenery into the fight. Gladiators—often slaves or condemned criminals—could win freedom, but most died young. Games continued until the 6th century; later the ruin was quarried for stone to build Renaissance palaces. Today two-thirds of the original structure survives as the enduring symbol of imperial Rome.