Archaeologists Found a Lost Roman Fort That May Solve a 1,700-Year-Old Mystery

The Roman emperor Magnus Maximus ruled territory stretching from Spain to Britain in the late fourth century C.E. Medieval folklore also alleged he made it to Wales as well, pitching camp on the easternmost peak of the Preseli Hills—but that story has always been treated as a myth. Until now. Well, possibly.

Mark Merrony, a supernumerary fellow in archaeology at the University of Oxford, wrote that he’s found evidence putting Maximus in Wales, along with an army garrisoning a fort built roughly three centuries earlier.

The Welsh chapter of Maximus’ story begins with another story: the medieval collection of Welsh tales known as the Mabinogion. Experts have long held that the fourth-century ruler called Macsen Wledig in those writings stands in for Maximus. “The Dream of Macsen Wledig” recounts the emperor’s rise to power and tells how he dreamt of a beautiful woman, then crossed the sea to Britain to find her and win her hand. In the course of his military maneuvers there, the tale says, he climbed Frenni Fawr, the 1,300-foot easternmost peak of the Preseli Hills. “There the emperor pitched his tent,” according to a translation quoted by Smithsonian magazine.

Merrony believes the legend is more than folklore, and he recounted his own quest for Maximus in The Conversation. That search began in 2002, when he excavated a Roman villa first found in the 19th century, about 18 miles from the site where he now believes he’s identified a fort—one built in the first century and, he argues, later repurposed by Maximus and his troops.

“If Magnus Maximus was there, there must have been an army there,” Merrony told The Guardian. “It’s such a remote area but the tale mentions the easternmost peak of the Preseli Hills, which is where this site is. The presence of a heavily fortified Roman auxiliary fort may help unlock the mystery of a Mabinogion legend that has endured for nearly 1,700 years.”

The trail that led him there started at the villa. While working at the site, Merrony was asked by a colleague why such an impressive Roman building stood in an otherwise remote corner of Wales. The question sent him looking for a major Roman road nearby, and in 2022 he had what he calls a breakthrough: he traced sections of a Roman road, which in turn pointed him and others toward additional villas.

“My observations have attracted a good deal of skepticism, but my heart and mind felt that I was making considerable progress tracing the Roman road network from Pembrokeshire east into Carmarthenshire,” he wrote.

Then, while examining satellite imagery in 2024, Merrony spotted what he took to be the telltale outlines of a Roman auxiliary fort beside the probable line of that road, near Crymych in north Pembrokeshire. “The earthworks had a characteristic playing-card shape like auxiliary forts and were about three hectares in area, which is typical for this type of military installation,” he wrote.

Surveys on the ground followed, turning up Roman pottery and other scattered finds. “Our breakthrough came in early September with the excavation of five trenches,” he wrote. The team identified the site’s principal buildings—the commander’s house, a headquarters building, and granaries—along with the clay bases of floor structures packed with thin stone slabs, diagonal alignments of stones, further pottery shards, and a kiln filled with fragments of Roman ceramic tile. One trench cut across the base of a rampart.

The excavation also produced a lead spindle whorl, an iron stylus of the kind used to write on wax tablets, a woodworking axe, a gaming counter, a third-century coin and two coins from the later fourth century, Maximus’ own period. “The collective findings indicate that the site was once a typical timber fort,” Merrony wrote, adding that it was probably established during the campaign of the governor Sextus Julius Frontinus between 74 and 78 C.E.

If that earlier governor built the fort, Maximus could simply have taken it over and spared himself the trouble of building a new one, Merrony wrote. He plans to publish his findings in Antiqvvs, the magazine he founded, and to write a book about the discovery.

“The discovery represents an extraordinary fusion between myth and reality,” Merrony wrote, “and demonstrates that folklore is often underpinned by fact.”