Fidenae

I thought this stadium disaster was really interesting:

>In 27 AD, an apparently cheaply built wooden amphitheatre constructed by an entrepreneur named Atilius collapsed in Fidenae, resulting in what was said to be the worst stadium disaster in history, with at least 20,000 killed and many more injured out of the total audience of 50,000.[7][8]

＞The emperor Tiberius had banned gladiatorial games, and when the prohibition was lifted, the public had flocked to the earliest events, so a large crowd was present when the stadium collapsed. At the time of the incident, Tiberius was in Capri, where he had a secure getaway, but he rushed to Fidenae to assist the victims of this incident.[9]

＞The Roman Senate responded to the tragedy by banning people with a fortune of less than 400,000 sesterces from hosting gladiator shows, and also requiring that all amphitheatres built in the future be erected on a sound foundation, inspected and certified for soundness. The government also "banished" Atilius.[10]

＞A digital reconstruction found the reported casualties to be consistent with a wooden structure similar in size to the still-standing stone structure of the amphitheatre in Verona.[11]