RW: The Arena, located outside the city walls, is a Roman amphitheatre built in the first half of the first century A.D. It is the third largest building of its type and is the most well preserved. It has been used to host games and battles, plays in the 12th century, jousting in the Middle Ages, and in 1913, it became the largest operatic theatre in the world. The acoustics and the sheer size of the place lend themselves well to grandiose operatic performances, amongst which the performance of Giuseppe Verdi's 'Aida' is particularly famous. The interior is open to the public.