ARCHAEOLOGISTS have discovered a 2000-year-old prehistoric settlement at the site of a new prison in Inverness.

An excavation carried as part of the development of the new HMP Highland uncovered 16 roundhouses, which are believed to have been occupied in the Bronze and Iron ages.

Clay moulds, whetstones for sharpening tools and metal artefacts made of copper-alloy material have all been found at the site, with archaeologists also unearthing holes where timber posts supporting the “substantial” roundhouse buildings would have once stood.

Pottery and worked flint were also discovered during the excavation, which is being conducted by AOC Archaeology Group alongside contractors from UBCivils and Balfour Beatty on behalf of the Scottish Prison Service (SPS).

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"The collaboration was made possible by the support of Scottish Prison Service," said Mary Peteranna from AOC Archaeology Group.

"They facilitated the process of safeguarding the archaeology on the site and have been fully supportive of presentation of the results so that it is available for the public.

"This is a truly important part of the cultural heritage of Inverness."

The new HMP Highland will replace Inverness Prison, which is more than 120 years old and deals with inmates whose sentences were handed down by courts in the Western Isles, Fort William, Elgin and Wick.

Archaeologists stand in holes that would once have held wooden posts used to support a roundhouseArchaeologists stand in holes that would once have held wooden posts used to support a roundhouse (Image: AOC Archaeology Group)

It will increase capacity from 103 prisoners to 200 and is expected to cost around £209 million.

“This discovery encapsulates the importance of the site to the community of Inverness, both historically and in the present day,” said Lorriane Roughlan, an SPS project executive for HMP Highland.

The prison site is situated within a landscape where other important archaeological finds have been made, including an Iron-age craftworking centre at Culduthel.