The excavation was led by Gary Bankhead, president of the Vedra Hylton Community Association and honorary fellow of Durham University’s Department of Archaeology.
He said the whetstone production site was the largest in Britain, “without a shadow of a doubt”.
“It’s probably the largest number of whetstones found in the entire north-west of Europe,” he said, “so it’s a significant location, hidden in plain site.”
Bankhead said the team had also uncovered several other objects from different periods which suggested Offerton was abandoned after the Romans left but later re-established as a settlement.