It was designed by Peddie and Kinnear in the Scottish baronial style, built by John Coghill & Co in ashlar at a cost of £8,386, and was officially opened by Sheriff Patrick Fraser on 5 November 1869.

[1] The Governor's House, standing to the southwest of the main building, survived but was later sold for private residential use.

[7] In October 1999, the building was the venue for a high-profile trial involving three women accused of boarding a Trident support vessel in Loch Goil and throwing computer equipment overboard.

Sheriff Margaret Gimblett, having controversially deemed nuclear weapons to be illegal under international law, instructed the jury to find the three women not guilty.

A few months later, in the High Court of Justiciary in Edinburgh, Lord Hardie ruled that the defence was mistaken.