In Piazza Bra there are various buildings of different ages and different architectures. Palazzo Barbieri, council offices, it's a neoclassical building built between 1836 and 1848 and inspired by the shapes of ancient Roman temples. On the right there is still a portion of the city walls built by Gian Galeazzo Visconti in the late fourteenth century, during the Lombard domination over the city. But the Arena is the monument which, more than any other, recalls the origins of the Roman city and is its symbol in the world. A huge amphitheater, the third largest among those still existing and anyway the best preserved, although in 1183 an earthquake has destroyed the third row of overlapping arches that surrounded it entirely and which today remains only a glimpse. Erected in the first century A. D. with marble taken from quarries in the province, is an ellipse 110 mt. long and 140 mt. wide, made an uninterrupted sequence consists of 72 double stone arches. Arena was used for gladiator fights and performances of all kinds: tournaments, jousts, duels, ballets, circuses, hot air balloon ascensions and even bullfights; since the summer of 1913 it hosts the largest open-air opera season of the world, with six hundred thousand spectators. During the Christmas period, Piazza Brà hosts a huge comet that comes from the Arena, and on the occasion of the celebrations of St Lucia (10/13 December), there are stalls with cakes, toys and handcrafts.