The area immediately outside the western walls of the city, close to the arena where Spartacus had fought (later demolished), underwent large-scale reorganisation at the end of the first century AD. The site was used to build the largest amphitheatre in western Europe after the Colosseum, an extraordinary theatrical venue that could hold up to 60,000 spectators. Originally 44 metres high, the amphitheatre had four floors, built entirely using tuff from mount tifata. It was a majestic work of engineering due to its functional design and the clarity of its architectural, hydraulic and 'hygienic' solutions. The arena providing the setting scenery and props, the stars and technicians of the shows, ferocious beasts, gladiators and ritual areas.