Near (5 km.) modern Capua. Built in the time of Augustus, restored by Hadrian and dedicated by Antoninus Pius, as the inscription over the main entrance recorded. The exterior was formed by 80 Doric arcades of four stories each, but only two arches now remain. The keystones were adorned with heads of divinities, an unusual amount of sculptural decoration. The seats are now gone. The interior is better preserved; beneath the arena are subterranean passages and extensive service quarters. It is second only in size to the Colosseum in Rome.