In addition to these literary data, archaeology sheds light on the pre-Roman past of this city.  Its trade with both the surrounding region and the Mediterranean world, as confirmed by numerous evidence, dates back to at least the 3rd century BC. In Roman times, the legal status of Pheradi Majus changed gradually. From Oppidum in the time of Caesar, it was elevated to the rank of municipium in the 2nd century and then, at an unknown date, to the rank of the honorary colony.

In late Antiquity, prominent Byzantine historian Procopius of Caesarea, in his work Bellum Vandalicum (History of the Vandal Wars), refers to the wealth of the Pheradi Maius region at the time of the Byzantine conquest. In the current state of research, very few material traces of Christianity are attested. However, two bishops of Pheradi Majus are known in 411 and 484.

Access to the site is made via a small path that leads to the monumental gate, which represents the entrance to the civic center. The excavations of Pheradi Maius were limited to this sector of the town where the main public buildings and facilities are concentrated.

The public baths: This is the first monument encountered by visitors to Pheradi Maius. Covering an area of about 500 square meters, the baths consist of several rooms: a vestibule, semicircular latrines, a large room decorated with mosaics, a frigidarium, a tepidarium, and a caldarium.

The Monumental Gate: access to the monumental center of Pheradi Maius is from the north side through an imposing gate consisting of an arch resting on two pedestals. Each pedestal is decorated on the outside with a niche that was supposed to house the protective deities of the city.  

The Market: after passing through the monumental gate, one discovers the market on the left. Consisting of a courtyard surrounded by a paved portico, it has five shops, on the north side, and three shops on the east side.

The Forum: Pheradi Maius is one of the few cities in Roman Africa with two public squares. A lower, older square, taking the form of a large paved esplanade, is located below the forum. Then, the forum square itself, oriented East-West and surrounded by a portico to the south, east, and north.                                                                                                                                                                                         

Religious buildings: as the location of the city was determined by the existence of a freshwater source, a Nymphaeum was built in Roman times. Situated between the two squares, this fountain is composed of five arches each housing a basin. The base of a statue, certainly that of Neptune, was found in the cella at the bottom of the central basin. The top of the hill to the east of the monumental center was used for the erection of a temple dedicated to the "geniuses of the place". It was transformed into a fortress in the Byzantine period.

The Amphitheatre: built at the western end of the site, it is oval with a 55 m long axis and a 40 m short axis.

The entire area between the forum and the amphitheater, a large residential area under the High Empire, was transformed into a craft district that witnessed a particular boom during the Vandal period. Fine ceramics and, in the Byzantine period, also lime was produced here. The cessation of these activities in the second half of the 7th century marked the beginning of the ultimate demise of the ancient town of Pheradi Maius.