A 10th century fire which devastated an important Pictish fort in Moray created a treasure trove for archaeologists, researchers have discovered.

The destruction of Burghead Fort, often attributed to Viking raiders, spelled the end for Pictish civilisation in the area.

However, the fire also led to the preservation of material that would otherwise have rotted away hundreds of years ago.

Now, a team from the University of Aberdeen is sifting through the results of a new excavation at the site near Lossiemouth.

Among the new discoveries is a huge timber laced wall standing more than six metres in height which throws fresh light on the fort's defences.

Dr Gordon Noble, the university's head of archaeology, explained: "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."

In addition to the defensive wall, the team has discovered intricate hair and dress pins and a "midden layer", or Early Middle Ages rubbish tip.

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.

Dr Noble added: "What's exciting is the level of preservation here. We've found animal bone which rarely survives in mainland Scotland because of the acidic soil.

We are already getting really nice information about what people ate within the fort and we hope to extract a level of information we've not had for Pictish sites before."