One of the most iconic landmarks of the Eternal City, the Colosseum attracts millions of tourists every year. The 2-millenia-old structure is located in the historic centre of Rome. With a capacity of about 60,000 spectators, it was the biggest amphitheatre in the Roman Empire. Oval in shape, the huge amphitheatre was used for gladiator tournaments, animal fights, executions of prisoners, games, circuses, theatrical performances, etc. It is an exceptional and phenomenal piece of history and architecture, so don’t miss it when in Rome. But, due to the large number of visitors, consider buying "skip the line" tickets.