The Stadion, c. 330 BC, restored for the first modern Olympics in 1896, Athens, Greece, Europe

Roman amphitheatre, Nimes, Gard, Occitania, France, Europe

Corridas arena, Alicante, Valencia province, Spain, Europe

The Roman Amphitheatre, Arles, UNESCO World Heritage Site, Bouches du Rhone, Provence-Alpes-Cote d'Azur, France, Europe

Colosseo, Rome

Staigue stone fortification, Iveragh peninsula, Ireland

The Lanxess Arena in the Deutz district, Cologne, North Rhine-Westphalia, Germany, 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