Rome’s famous 2,000-year-old Colosseum has a vast underground world called the “hypogeum” and it’s now open to the public for the first time. The Colosseum, or Flavian Amphitheater, was a gigantic structure that opened in 80 AD to provide entertainment to 50,000 of Rome’s population. According to Rome.net, construction of the Colosseum began under Emperor Vespasianin […]