Archaeologists investigating the Roman city of Aquinum in central Italy are uncovering new evidence of how the ancient settlement functioned, from an extensive underground network of sewers and drainage channels to ritual inscriptions, a Roman altar and a hoard of more than 100 coins.
Aquinum is under agricultural fields near modern Aquino in Frosinone province about 60 miles south of Rome.
Once one of the most important Roman centres along the Via Latina between Rome and Capua, it covered an estimated 250 acres. Archaeologists have excavated only about 20 acres after 18 years of research by the University of Salento.
Since 2020, Roma Sotterranea researchers have been working alongside archaeologists to look at another part of the city which is largely unseen: its underground infrastructure.
Exploring beneath Aquinum
Roma Sotterranea specialises in exploring subterranean archaeological structures such as sewers, cisterns, drainage channels and inspection shafts.
Between 2020 and 2023, the team documented more than 790 feet of underground conduits beneath Aquinum’s Central Baths.
The network includes channels and wells that formed part of the hydraulic infrastructure required to manage water beneath the Roman city.
Since 2024, investigations have concentrated on Aquinum’s theatre, which is believed to have accommodated approximately 5,000 spectators.
Although archaeologists can reconstruct much of the theatre’s architecture from surviving remains, its underground infrastructure remains poorly understood.
“The architecture tells us what the theatre looked like,” said Francesco Artibani, project director of Roma Sotterranea. “What we are searching for underground can help us understand how it actually worked.”
Main sewer located in 2026
Separately from the earlier work beneath the baths and the ongoing investigation of the theatre, researchers located Aquinum’s main sewer collector earlier in 2026.
The sewer lies beneath the intersection of the Cardo Maximus and Decumanus Maximus – the principal north-south and east-west streets of the Roman city.
The underground structure measures approximately 4.5 feet wide and more than seven feet high.
Investigations also uncovered a hoard of 120 coins, inscriptions and pottery. The available account does not specify more precisely when during 2026 these finds were made or whether all were recovered directly from the sewer itself.
Researchers have increasingly used technology to explore underground spaces that are difficult or unsafe for people to enter.
A robotic inspection system equipped with a cable extending up to 330 feet has been introduced alongside ground-penetrating radar surveys, allowing researchers to investigate buried conduits without excavating them completely.
Evidence of Roman religious rituals
The 2026 excavation season has also produced several unusual discoveries elsewhere at Aquinum.
Among them is a carved stone cippus depicting an ox, ram and pig.
The three animals are associated with the suovetaurilia, one of the most important sacrificial ceremonies in Roman religion, during which a pig, sheep and bull were sacrificed.
The stone had subsequently been reused as paving at an important crossroads within the city.
Archaeologists also discovered a marble altar dedicated to the Genius of Augustus.
An inscription records that it was financed by Manius Popidius Anteros, a wealthy freedman who had become a sevir Augustalis, a member of a civic religious organisation closely associated with the imperial cult.
‘Buried lightning’ inscription
Another unusual discovery came from the city’s theatre.
Archaeologists uncovered a marble slab inscribed with the formula FVL(GVR) C[ONDITVM], meaning “buried lightning”.
In Roman religion, places struck by lightning could be regarded as sacred. Material associated with the lightning strike could be ritually buried and the location formally marked or consecrated.
The inscription therefore provides evidence for religious practices taking place within or around Aquinum’s theatre.
The 2026 season has also included the restoration of five marble portrait heads discovered at the site, including a sculpture known as the “Caesar of Aquinum”.
One of the largest cities on the Via Latina
Aquinum occupied an important position on the Via Latina, the ancient road connecting Rome with southern Italy.
The city became a prosperous Roman centre and was known for producing purple dye, an industry referenced by the Roman statesman Cicero.
Aquinum is also traditionally associated with the Roman satirist Juvenal, who referred to the city in his writings.
Centuries later, the surrounding territory became associated with Thomas Aquinas, whose family held the nearby castle of Roccasecca and whose name derives from Aquino.
Excavations have already revealed substantial evidence of the Roman city’s wealth, including a large bath complex containing exceptionally well-preserved mosaics.
Yet most of Aquinum remains untouched beneath modern farmland.
“There is something extraordinary about looking across those wide stretches of land, now cultivated and ploughed, and realising that an entire city still lies underneath,” said Artibani.
“A city that, for the most part, will remain there, buried and preserved in the ground.”
With only a fraction of the approximately 250-acre settlement investigated, much of Aquinum’s streets, buildings and underground infrastructure remains concealed beneath the surrounding fields.
Sources : Ancient Rome Live
