Nimes, Languedoc-Roussillon, France

The ancient Roman Arena in Nimes is the 20th largest of the 400 still in existence. It is famous because it is (allegedly) "the best preserved." It was built in the 1st Century A.D. and in its heyday held 24,000 spectators to watch gladiator matches and other blood sports. It's still used for concerts and bullfighting. Apparently, Napoleon's wife was heavily into bullfighting and brought it to France from Spain.