Probably the most important building of the Roman period still visible in Sardinia. It's almost entirely carved in the sloping rock, using the natural valley that goes down from Buon Cammino. It was built between the 1st and 2nd century AD and it could originally seat up to 10,000 spectators. The terraces were divided into three different orders, depending on the spectators' social class. The shows included fights between gladiators, or against wild beasts, which were kept in cages, at the sides of the arena, and still visible today. The walk along Buon Cammino to get there is magnificent and offers beautiful views. A downhill stroll takes you back to piazza Yenne.