Ancient Roman factory found on English riverbank

By Stephen Beech

Evidence of a Roman industrial hub in North East England dating back over 1,900 years has been unearthed.

The "extraordinary" discovery at the Offerton site, on the banks of the River Wear near Sunderland, has so far yielded more than 800 whetstones and 11 stone anchors.

Analysis of the sediment layer containing the whetstones - stone bars used to sharpen bladed tools and weapons - has confirmed the site dates to the Roman era.

The site was discovered and excavated by volunteers from the Vedra Hylton Community Association, and supported by Durham University’s Department of Archaeology.

The find represents the largest known whetstone discovery of the period in North West Europe.

Experts say whetstones were "vital" tools in every aspect of Roman life – from the domestic and commercial to the agricultural, industrial, medical, and military.

The abundance and condition of the whetstones discovered, along with a corresponding sandstone outcrop on the opposite side of the river, indicate Offerton was likely a major production hub in Roman Britain.

The site has been dated using Optically Stimulated Luminescence (OSL) testing on the sediment layers surrounding the whetstones.

OSL measures when minerals such as quartz were last exposed to sunlight.

The minerals build up a tiny store of energy over time while buried.

When stimulated with light or heat in a lab, the minerals release that energy as a faint glow, which tells experts how long they have been underground.

The results showed that sediment samples taken directly below the whetstone discovery were dated to 42AD to 184AD.

The sediment sample taken from the whetstone layer was dated to 104AD to 238AD – during the Roman occupation of Britain.

Archaeologists say the results suggest Offerton is the first Roman site found in Britain where stone was deliberately quarried for whetstone production.

Alongside the 800 whetstones excavated, the team believe that there are hundreds, possibly thousands, more that remain buried within the riverbank.

The project team undertook excavation works along the riverbanks and foreshore at Offerton, with support from The Crown Estate.

Over the course of six months, the team found the vast haul of whetstones in various stages of production, from roughly worked pieces still bearing tool marks to finely finished examples with smooth surfaces and chamfered edges.

The team also found 65 "doubles" – whetstones still conjoined prior to splitting – along with a rare "treble".

The recorded whetstones are all damaged and were likely discarded during production as they no longer met the required length.

The Roman army were particular about the uniformity of their equipment so any whetstones that were not exactly 12 inches would have been discarded, say historians.

Five stone anchors were also unearthed by the fieldwork team during 2025.

Six stone anchors had been recovered in the adjacent stretch of river in 2022, bringing the total to 11 - the largest number of stone anchors ever found at any northern European river site.

The Durham University team believe the anchors could have been used by river going vessels that were transporting slabs of sandstone across the river for whetstone preparation.

The team also discovered a post-medieval wooden jetty structure, and earlier stone-built jetty; tools including chisels and stone splitters; a leather shoe from Tudor times, plus iron and stone cannonballs, and lead shot dating to the English Civil War.

The discoveries suggest the riverside site held greater strategic importance than previously understood.

The wooden jetty and associated small finds may relate to the women known as “hailers” who once hauled keel boats upriver, according to the team.

Skippers would literally “hail” for their help as vessels headed upstream to collect coal, often struggling against the tide and wind.

Together the findings could extend the known timeline of human activity along that part of the River Wear by over 1,800 years, according to the research team.

The project was led by Gary Bankhead, President of the Vedra Hylton Community Association and an Honorary Fellow at Durham University’s Department of Archaeology.

He said: “This isn’t just a Roman site - it’s Sunderland’s story, revealed through the dedication of local volunteers and researchers working side by side.

"The River Wear has once again offered us a remarkable discovery, and we are only beginning to understand its full legacy.

“At Offerton, the recovery of Roman coins, along with firm OSL dating, now confirms the site’s Roman origins.

"Here, we see compelling evidence of one of Sunderland’s earliest known industries.

"The manufacture of whetstones at this location closely matches examples from securely dated Roman contexts, demonstrating that whetstones were being produced - and very likely distributed - from this riverside workshop.

“It is another extraordinary chapter from a river that continues to rewrite history.”

Dr. Eleri Cousins, Assistant Professor in Roman Archaeology at Durham University, said: “This site has the potential to make a significant addition to our understanding of manufacturing and industry in Roman Britain, particularly in the militarised north of the province.

“This is an exciting discovery that tells a fascinating story about how ordinary objects like whetstones could be produced on an industrial scale.”

Cllr Michael Mordey, Sunderland City Council leader, said: “Ships, coal, pottery, glass and cars have all been made on the banks of the River Wear over the years by generations of Sunderland families.

"Thanks to the results of research and analysis carried out by experts at Durham University, this work has revealed yet another generation of makers who have shaped the industrious city we are today."

He added: “This shines a whole new light on the role Sunderland may have played in the Roman Empire."

The excavations will be featured in the new series of "Digging for Britain" on BBC Two and available on iPlayer from today [WED].