Archaeologists have unearthed the remains of a roofed theatre, market and river port at the site of a Roman town.
The Cambridge University-led study suggested that Interamna Lirenas, in central Italy, was a thriving town.
Finds at the site have suggested its decline began about 300 years later than experts previously thought.
Analysis of excavated pottery indicated the town in southern Lazio resisted decline until the later part of the 3rd Century AD.
At its peak, the settlement, which is now largely crop fields, would have housed about 2,000 people, according to the study.
“We started with a site so unpromising that no-one had ever tried to excavate it – that’s very rare in Italy,” Dr Alessandro Launaro, the study’s author said.
“There was nothing on the surface, no visible evidence of buildings, just bits of broken pottery. But what we discovered wasn’t a backwater, far from it.
“We found a thriving town adapting to every challenge thrown at it for 900 years. We’re not saying that this town was special, it’s far more exciting than that.
“Dr Launaro, who is the Interamna Lirenas project lead at Cambridge’s Classics faculty, said archaeologists had previously assumed the town was a declining backwater.
The research team conducted a series of digs and carried out a magnetic and ground-penetrating radar (GPR) survey of about 60 acres (24 hectares).
The survey, near the River Liri, revealed the presence of a large warehouse, a temple and a bath complex, with the researchers confident these structures served a river port between the late 1st Century BC and the 4th Century AD.
The team also discovered the remains of a roofed theatre, which could have seated 1,500 people.
It displayed the town’s wealth, power and ambition, Dr Launaro said.
The archaeologists also found 19 courtyard buildings and land they believed served as a cattle and sheep market.
They did not find a layer of ash or any other evidence to suggest the town was violently destroyed.
Dr Launaro argued that inhabitants deserted the town amid growing insecurity before the Lombard invasion of the late 6th Century AD, because they knew they were on a direct route which marauding armies were bound to use
