The hidden secrets of one of Scotland’s oldest historical sites are set to be revealed after lying untouched for centuries.

Dunyvaig Castle on Islay was once a stronghold of the Lord of the Isles, the chiefs of the Clan MacDonald, and was the scene of many battles between them and rivals the Campbells.

However, it is believed that the site dates back even further to prehistoric times when it was used as an ancient fort.

A team of archaeologists now hope to uncover the history of the landmark, which was demolished in 1677, in a ground-breaking project which will see its grounds excavated for the first time.

The project is the culmination of years of planning and fundraising by Professor Steve Mithen and his team at charity Islay Heritage, who hope to provide an insight into what life was like at the castle.

Mr Mithen said: “This is a hugely significant project for Scotland. We are excited about finding what secrets remain hidden underground about this iconic monument.”

The archaeology expert added: “One of the main questions we want to answer is what the castle was used for. We know it was a naval fortress, but was it also used for entertainment, for example. Are we likely to find a great hall where they might have entertained other lords?

“Or perhaps it was a commercial centre? Trade during the medieval period was hugely important so we could discover evidence of this.

“We also want to look at whether we can identify the destruction described in historical records. In the 16th century the Campbells bombarded the castle to defeat the MacDonalds, so we’ll be looking for evidence of that.

“When you dig into the ground you never know what you’re going to find.”

A team of around 40 experts, including leading archaeologists, geophysicists, scientists and environmentalists, will take part in the initial three-week excavation at the castle, which sits in Lagavulin Bay.

Mr Mithen believes they will be able to access underground structures and objects relatively easily as the site has not been developed in the way other historic sites have been.

The project will also see local schools and community groups invited to the site to see what has been discovered, and will be used to train current archaeology students in survey and excavation methods.

Mr Mithen said: “We really want people on Isla to take an interest in their heritage. It’s an archaeological project for all.”

John Raven, of Historic Environment Scotland, added: “We warmly welcome this innovative project to raise money to support Islay Heritage and its aims of raising the profile and condition of, and increasing access to, Islay’s spectacular and unique archaeology, history and culture.

“It is a fantastic opportunity for heritage to make a greater contribution to the island’s economy.

“Dunyvaig Castle holds a deeply important place in Gaelic culture, and the excavations should help us better understand Medieval Gaelic culture and inform the castle’s conservation, so that it can be preserved and access opened up in the future.

“We can’t wait to see the results.”

The project has been part-funded by the Lagavulin 200th Legacy fund, a scheme by the Diageo distillery to raise money for community projects through the sale of a special bottling of Lagavulin malt whisky.

Dr Nick Morgan, head of Whisky Outreach at Diageo, said: “We’re looking forward to seeing what interesting discoveries will be uncovered over the next few weeks.”

Islay Heritage hope to raise further funds to allow excavation work to continue over the next five years.