Man Made Disasters

 It occurred in 27AD, in the town of Fidenae located close to Rome, Italy. Atilius, a local entrepeneur built a wooden amphitheatre on the cheap to celebrate the end of Emperor Tiberius ban on Gladiatorial Games, the construction was rushed in order to meet deadlines.  During the opening ceremony it collapsed, killing 20,000 blood-thirsty spectators. This is by far the worst stadium disaster in history and resulted in the Roman Senate passing laws that only citizens with wealth exceeding 400,000 sesterces would be allowed to host gladiatorial games and that all amphitheatres were to be erected on sound foundation. Atilius was banished from the Empire.