Under three feet of soil in a historical park in Wales, archaeologists say, lies what could be the county’s largest known Roman villa.

While conducting geophysical surveys of the site in the neighborhood of Margam in Port Talbot, researchers from ArchaeoMargam—a collaborative project by Swansea University, Neath Port Talbot Council, and Margam Abbey Church—“struck gold,” they said. Their ground-penetrating scanning devices uncovered the footprint of a Roman complex of a size and state of preservation unprecedented for the region.

“This is an amazing discovery,” Alex Langlands of Swansea University, who leads the project, noted in a statement. “We always thought that we’d find something dating to the Romano-British period, but we never dreamed it would be so clearly articulated.”

Footprint of the Roman Villa within its defensive enclosure (left) and an interpretative record of Ground Penetrating Radar survey of villa site (right). Photos: Terradat.

According to the team, the 6,156 square foot structure houses six main rooms at the front, with two corridors leading to eight rooms at the back. The home sits within a walled enclosure, measuring about 141 by 180 feet, which was likely the remains of an earlier Iron Age defense. An aisled building, possibly used as a storage facility or meeting hall, sits to the southeast of the main villa. (The precise location of the find is being kept under wraps for now.)

Speaking to the BBC, Langlands posited that the villa could have housed a local dignitary. As “the centre of a big agricultural estate,” he said, it would have bustled with visitors.

“It is too early to speculate about the date range of the building, its architectural features, who constructed it, and how it fell out of use,” he added in a statement. “But from the geophysical survey alone, we can start to build hypotheses about how important this site could be and what it can tell us about Margam’s long-term role in the social, cultural, and economic developments across the first millennium in Wales.”

Researchers at the Margam site. Photo courtesy of Swansea University.

Margam has long been the site of prehistoric discoveries from Bronze Age burial mounds to Iron Age hillforts. Its Medieval history can also be traced in its surviving inscribed stone monuments, dating to Early Christianity around the 6th century, some of which are held by the Margam Stones Museum. The remains of its 12th-century abbey further reveal a Celtic monastic heritage.

But there is scarce evidence of Margam’s Roman occupation from 48 C.E.—save for remnants such as a milestone carved with the name of Roman Emperor Postumus, now in the National Museum of Wales in Cardiff. This new discovery, then, presents a “missing piece of the puzzle,” Langlands said. The site might even turn out to be “Port Talbot’s Pompeii,” he playfully suggested to the BBC.

“Wherever you get villas like this, they’re almost certainly surrounded by other edifices of the period,” Langlands said in a video accompanying the university’s announcement. “We’ve probably got trading centers here; we know we’ve got the Roman roads here. There should be a bathhouse somewhere and almost certainly, there’ll be other small Roman farmsteads. So it really does change the story.”