The was planned under the Emperor Vespasian and dedicated in 80 C. E. as an amphitheater for gladiatorial games and public entertainments. A large oval covering 6 acres, the could accommodate some 50,000 spectators-about the same number as most major-league baseball stadiums today.

The answer is the Colosseum

Explanation:

The largest and most famous symbol of the Roman Empire, the Colosseum was a huge amphitheater reserved for gladiatorial battles or against these warriors against wild animals. Sumptuous, it was more comfortable than many modern stadiums. Its construction was started in 72 AD, by order of the emperor Vespasiano, who decided to build it on the site of an old palace of Nero, his predecessor in command of the empire.

julius caesar turned the roman republic into the roman empire by coming in and taking the "dictator" role during the time of a civil war (elites vs lower classes) winning battles and reputation, then declaring him dictator for life

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