The Underground of the Flavian Amphitheater, the third largest Roman amphitheater in Italy, Pozzuoli, Naples, Campania, Italy, Europe

The Underground of the Flavian Amphitheater, the third largest Roman amphitheater in Italy, Pozzuoli, Naples, Campania, Italy, Europe

Colosseum (Flavian Amphitheatre), UNESCO World Heritage Site, Rome, Lazio, Italy, Europe

Colosseum (Flavian Amphitheatre), UNESCO World Heritage Site, Rome, Lazio, Italy, Europe

Close-up of a Christian cross inside the Roman Colosseum against a blue sky, erected by the Pope in 2000 to commemorate Christian Martyrs; Rome, Lazio, Italy

Close-up view of the iconic Colosseum against a blue sky; Rome, Lazio, Italy

Overview of the inside of the iconic Colosseum against a blue sky with crowds of tourists sightseeing; Rome, Lazio, Italy

Close-up view of the iconic Colosseum against a blue sky, showing a marble plaque above the East Entrance dedicated to Christian martyrs; Rome, Lazio, Italy