Amphitheatre Flavio at

The Amphitheatre Flavio is the third biggest of the Roman world, after those of Rome and . It was located at a crossroads which linked , Capua and Cuma and built by the architects of the Colosseum, under the rule of Vespasian and perhaps inaugurated under Tito. Capable of holding up to 40.000 spectators, its three levels were furnished with four main entrances and twelve secondary entrances. As well as being an entertainment arena, the amphitheatre was also a centre of urban life. Under the external arches of the structure there existed a range of outlets dedicated to cults, professional and other groups, all indicated by inscriptions on the stone. It is particularly rewarding to visit the subterranean complex which gives a good idea of the sort of services and general organisation that must have been required for the functioning of the amphitheatre. Such grandeur testifies to the extraordinary technical skills achieved by the ancients.

The interior is mostly intact and one can still see parts of gears which were used to lift cages up to the arena floor. The elliptical structure measures 147x117m (482x384ft), with the arena floor measuring 72.22x42.33m (237x139ft).

In 305, the arena was the setting for the persecutions of the patron of Pozzuoli, Saint Proculus, and the patron saint of Naples, Saint . After surviving being thrown to the wild beasts in the arena, the two were beheaded at the nearby Solfatara. In memory of the Saint a church was built in 1689. As result of the excavations of the Amphitheatre the church was dismantled and subsequently replaced by a small chapel which can still be visited.

It was abandoned when it was partially buried by eruptions from the Solfatara . During the Middle Ages, the marble used on the exterior was stripped, but the interior was left alone and is perfectly preserved.

The Flavian Amphitheatre is the second of two Roman amphitheatres built in Pozzuoli. The smaller and older amphitheatre (Anfiteatro minore) has been almost totally destroyed by the construction of the Rome to Naples railway line. Only a dozen arches of this earlier work still exist. This lesser amphitheatre measured 130x95m (427x312ft).

Rione Terra is the first city of Pozzuoli dating back to the 2ndC BC and it is an excellent example of urban stratification over the centuries. The Rione Terra is located on a hill to better control arrivals from the sea and Pozzuoli was considered the port of Rome, before the construction of Ostia. The area of the Rione Terra of Pozzuoli was completely evacuated in 1970, following a bradyseism (volcanic activity that increases and then decreases the level of the city compared to the sea) crisis, and for this reason it took on the features of a ghost area for many years.

The cathedral is built on the remains of the temple of Augustus and it reopened to the public in recent years, after numerous restorations.

The Temple of Serapis is a unique testimony to the dockland and commercial district of "Puteoli". So called for the statue of the god Serapis (which today is housed in the Archaeological Museum of Naples), the temple is one of the best examples of "macellum" – a food market – built between the end of the 1st and the beginning of the 2nd century AD and restored under the Emperor Severi in the 3rd century. The shops and boutiques were situated in lines in a courtyard which supported a large entrance gate and marble decorations. In the final line there was a hall with apses for the Imperial Cult and the protectors of the market, among whom was the divinity Serapis. Belonging to the "pronaos" of this "sacellum" are 3 marble columns which, with small pock marks made by molluscs which burrow into the stone, are superb examples of the geological phenomenon of bradyseism. The sumptuous edifice of the market is ornately decorated with beautiful marble and the "tholos" (a large circular building) at the centre of the courtyard, which has 16 columns made of African marble with striations in the lower parts made by marine animals. During 18thC excavations, a series of valuable sculptures including Dionysus with Faun were found and these are now housed at the Archaeological Museum of Naples.