Which city would you be in if you were visiting the Colosseum?

Explanation

The Colosseum in Rome was built as an amphitheatre and used, amongst other things, for gladiator fights. It fit 50,000 spectators and measures 188 metres x 156 metres. Today, only the northern part of the building is instact. The building rests on 80 large columns, more than 45 metres tall each.