Roman Fort Welsh Legend: Unearthed Roman Ruins in Wales

In the green hills of west Wales, archaeologists have uncovered a previously unknown Roman fort that may breathe new life into a Roman Fort Welsh Legend — the medieval tale of an emperor, a dream, and a military camp on a windswept hill. Spotted in satellite imagery in 2024 by Oxford researcher Dr Mark Merrony, the site lies beneath an overgrown field near Frenni Fawr in the Preseli Hills of Pembrokeshire. Excavations there have since turned up Roman pottery, roof tiles, an iron writing stylus and two coins from the late fourth century — the very era of the emperor at the heart of the story.

According to a statement from Wolfson College, Oxford, the discovery could lend archaeological support to a centuries-old Welsh legend. The intrigue lies in the location and the dating: the Mabinogion, a collection of medieval Welsh stories, associates this exact landscape with Maximus — Macsen Wledig in Welsh — a fourth-century Roman emperor said to have established a military presence there. The Oxford college cautions that more research is needed before any direct link can be claimed.

Merrony, a Pembrokeshire-born Roman specialist and Supernumerary Fellow at Wolfson, noticed the fort's telltale outline — a rounded-corner "playing card" shape — in satellite images. A first visit to the overgrown field turned up a Roman tile, the first of many finds. A geophysical survey then revealed substantial buried buildings and a road running through the site. The enclosure measures about 180 by 150 metres, large enough to have housed roughly 500 troops, making it one of the most significant Roman military sites yet found in west Wales. Merrony told The Guardian: "If Magnus Maximus was there, there must have been an army there." It joins a growing list of discoveries rewriting old maps of the past, like the seabed archaeology that revealed Australia's drowned ancient world.

A dig that keeps giving

The breakthrough came in early September, when the team opened five trenches across the suspected commander's house, headquarters building and granaries, with further cuts over a perimeter road and an upslope track. The first two trenches exposed clay floors packed with thin stone blocks, disturbed by decades of ploughing; the second also held a diagonal alignment of stones hinting at a later phase of civilian occupation. One trench yielded a kiln packed with fragments of Roman ceramic tile, while another exposed the base of the rampart and a road surface with wheel ruts still pressed into it below the plough soil. In a first-person account for The Conversation, Merrony described the dig as the moment the site moved from suspicion to certainty.

The finds list reads like a Roman soldier's lost-and-found: pottery sherds, building tiles, a lead spindle whorl, an iron stylus for writing on wax tablets, a woodworking axe, a gaming counter and a coin from the third century. But the headline finds are the pair of coins from the emperor's own century. They date from the lifetime of Maximus, the usurper emperor proclaimed by his troops in Britain in 383 and defeated and executed in 388 — the same window in which, according to the legend, he was camping his army in Wales.

There is a twist in the timeline, though. The fort was probably not built for Maximus at all: archaeologists believe it was founded during the campaigns of the governor Sextus Julius Frontinus, between AD 74 and 78, as Rome drove into the west of Britain. That makes the enclosure roughly three centuries older than the emperor of the legend. The fourth-century coins prove activity on the site in his era — reoccupation, perhaps, or a garrison that never fully left — but they cannot put the emperor himself there.

The Roman Fort Welsh Legend meets its sceptics

"The Dream of Macsen Wledig" tells how the emperor had a prophetic dream of a beautiful woman across the sea, sailed to Britain, found her and married her. On his military manoeuvres, the story says, he pitched his camp at Frenni Fawr, the 395-metre easternmost peak of the Preseli Hills. Merrony says the geography matches with unusual precision — he told the paper: "It's such a remote area but the tale mentions the easternmost peak of the Preseli Hills, which is where this site is." The fort sits about 3.5 kilometres south-west of the summit, and it is the only Roman military installation anywhere in the landscape the tale describes.

The sceptical case is straightforward, and Merrony makes it himself. Coins from the right century are not proof of a person: nothing at the site names Maximus, and the tale was written down centuries after the events it describes. Folk memory is a creative historian, and medieval storytellers loved to anchor their heroes in famous places. What the fort establishes is narrower but still remarkable — a substantial, heavily defended Roman military presence in precisely the landscape the story names, where none was known before.

This is the same dynamic that turned another ancient poem into archaeology. In the nineteenth century, Heinrich Schliemann used Homer's Iliad as a treasure map and dug up the city of Troy, proving that epic verse can preserve real geography. The Frenni Fawr discovery belongs to that family of finds — a story written long after the fact, pointing at a place that now has stone, tile and coin beneath the turf. It echoes other recent cases where digging has unsettled what we thought we knew, from the mystery medieval building found beside a lost royal palace to the thousand skeletons surfacing under a Copenhagen park.

Why it matters

For readers in Wales, the stakes are about more than one more fort on the map. The emperor of the tale is one of the few Roman rulers woven into Welsh origin stories, remembered in genealogies as well as the story as a founder-figure of Welsh kingship. If the legend preserves a genuine memory of Roman troops in the Preselis, it suggests medieval storytellers were working from real knowledge of their landscape, not inventing it wholesale.

Merrony's full research will appear in the journal Antiqvvs, and he is writing a book on the lives of the Roman emperors from Augustus to Romulus Augustulus. The dig was funded by Oxford University with support from public crowdfunding. Whether or not an emperor ever camped beneath the hill, this Roman Fort Welsh Legend has gained something it never had before: a fort in the ground. The name of the commander may stay lost to history — but for the first time, archaeology can point at the right hill and say the army was real.