Once completed in 2026, it will be Scotland’s first net-zero prison, with improved education and health facilities to help with rehabilitation.

It will be able to accommodate 200 prisoners, over 100 more than the design capacity of Inverness Prison that it will replace, allowing more adult men from the Highlands and Islands to be accommodated in their local area.

When the project was conceived more than 10 years ago it was expected to cost about £52m. This later rose to £92m and then to around £140m in February 2022 when Balfour Beatty was named preferred bidder for the project.

The construction contract signed with Balfour Beatty will create more than £60m worth of supply chain investment with local businesses.

Justice Secretary Angela Constance said: “Signing this contract marks a significant milestone for the Highlands.

“As with all large-scale national construction projects, Brexit, high-inflation and supply chain issues have had an impact on the initial estimated costs, which we have been working hard with the prison service and suppliers to keep to a minimum.”

Consultant BakerHicks has been involved in the project from the early stages after winning the concept design through the SPS framework in 2016. The firm also provided multi-disciplinary services on the project throughout the design stages, including architectural, civil & structural, mechanical & electrical, and principal designer services.