AS the Vikings sailed away, they probably thought they'd done a good day's work.

The Pictish fort behind them was ruined and ablaze, its defenders put to the sword and anything worth looting had been thoroughly pillaged.

But now archaeologists examining the remains of the 10th-century settlement at Burghead on the Moray coast say the attack by the Northmen has actually helped preserve the site and ensure it could be studied by future generations.

A team probing the ruins have been amazed by the detail of the structures left behind, which include a Pictish longhouse and a huge timber-laced wall which would have stood more than six metres high.

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The fort at Burghead is believed to have been one of the most powerful created by the Picts, and was the largest of its kind in Scotland.

In situ charred planks in the wall face

The raid which brought about its destruction probably spelled the end for a way of life for Pictish life on the promontory, and little archaeological work has been undertaken there as it was believed all significant evidence was destroyed when the building of the modern town commenced in 1805.

However, a team from the University of Aberdeen led by Dr Gordon Noble, head of archaeology at the University, returned to Burghead in April to continue excavations at the fort and have made a series of startling discoveries.

Dr Noble explains: “We are fortunate to have the descriptions of the site written by Hugh Young in 1893. He describes a lattice work of oak timbers which would have acted as an enormous defensive barrier and must have been a hugely complex feat of engineering in the early medieval period.

“In the years that have passed since he made his observations, the Burghead Fort has unfortunately been subject to significant coastal erosion and the harsh North Sea environment.

“But when we started digging, we discovered that while the destruction of the fort in the 10th century may not have been good news for the Picts, the fact that so much of it was set alight is a real bonus for archaeologists."

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The wall face of the Pictish fort at Burghead

Dr Noble added: We have discovered that the complex layer of oak planks set in the wall was burned in situ and that the resulting charring has actually preserved it in amazing detail when ordinarily it would have rotten away to nothing by now.”

In addition to the fortified wall, archaeologists also found Anglo Saxon coins of Alfred the Great and intricate hair and dress pins, one with a detailed bramble design.

A bramble headed dress or hair pin

A mace headed pin

They also identified ‘midden layers’ which they expect to yield significant archaeological value in assessing the economy and everyday lives of the fort dwellers.

The level of preservation has allowed the archaeologists to take multiple samples for carbon dating which should provide new insights into the period when the fort was built, its construction and final destruction.

“The Picts were a huge influence on northern Scotland but because they left no written records, archaeology is essential in providing answers in regard to their lives, influence and culture,” Dr Noble added.

“While it has long been known that Burghead was a very significant place, it was also assumed that its archaeological value had been largely lost due to the destruction caused by the building of the modern town.

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“Our work so far has shown that this is certainly not the case. Instead we are starting to build a picture of Pictish resources being out into this site on a scale we have never found evidence for before.”

The work at Burghead is supported by the Leverhulme Trust, the University of Aberdeen and Historic Environment Scotland.

Cathy MacIver of AOC Archaeology with a bronze ring from the excavations