One significant building that was constructed by the Romans is the Colosseum. This building is located in Rome itself. It was built beginning in 72 AD and ending in 80 AD, though it was added on to and modified in later years.
The major significance of this building is what it tells us about Roman society. The structure was used as an arena for various sorts of gladiatorial games. It was used for the “regular” gladiatorial games as well as for more elaborate games, some of which involved flooding the arena so as to allow for mock naval battles.
This structure shows us how important these blood sports were to the Romans. It shows that they were willing to devote considerable resources to creating a venue in which people could watch other people kill one another.