What they found

The earthwork known as Y Werthyr, near Amlwch on Anglesey, lies in a dramatic landscape, rich in archaeology. To the immediate west, aerial photographs show at least one rectangular crop mark; there's a standing stone in the farm (also called Y Werthyr) to the north west of the site; and to the east is the intriguingly named field, Pen Y Fenwent – or Cemetery Hill – beneath what appears to be a tumulus.

Time Team was seeking to date and identify this strange earthwork. Could the Team find evidence of how people lived here? Their houses? Their occupations? Their deaths? And what was the strange rectangle in the midst of the earthwork? Could this represent multiple phases of occupation – perhaps straddling the dramatic period in the island's history between the Iron Age and the Roman era?

It proved to be a difficult site from which to draw definitive conclusions. Geophysics surveys and Stewart's wider landscape research both pointed to extensive – and, for the archaeologists – complex occupation phases. But there was a paucity of clear dating evidence, with much of the prehistoric landscape having been stripped bare of potential finds by later ploughing.

The team was able to establish that the site had been in use at least 2,000 years before the Roman attack on Anglesey when a Bronze-Age burial was found in the centre of the earthwork. The earthwork itself was probably home to an important Iron-Age chieftain, although postholes uncovered inside it didn't provide conclusive dating evidence and weren't sufficient to give a clear picture of the structures to which they belonged.

What was clear was that this had been a significant Iron-Age settlement, with a complex network of ditches, embankments, tracks and fields dating from before the Roman invasion. The site appears to have gone out of use after this time, although a couple of stray Roman coins were found among the covering layers of earth.

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