Fairburn Tower was a former stronghold of the Clan Mackenzie had has links to the Jacobite Rebellion.
It was built in 1545 for Murdo Mackenzie, a close aide of King James V, the father of Mary Queen of Scots.
Set in dramatic landscape near Muir of Ord, 20 miles from Inverness, it is one of the few surviving examples of the short-lived Scottish Renaissance architectural style.
Its unusual height, the completeness of its walls and evidence of its original form make it a rare and important remnant of its time.
But the tower’s current condition is perilous, with giant cracks running the full height of its ancient walls.
Currently cordoned off to the public for safety, the structure is in imminent danger of collapse if repair work is not carried out.
Now the Landmark Trust has launched a fund-raising drive in a bid to restore the ruin, which has Scotland’s highest listed building status.
Historic Environment Scotland (HES), the agency responsible for the nation’s built heritage, has agreed to provide a grant of £455,000 to support the restoration project, which will cost around £1.82 million.
Dr Anna Keay, the charity’s director, said: “The cherished property, gift of the Stuart kings of Scotland, and Mackenzie’s noble tower now stands in desperate need. It has survived for over four hundred years, but if we don’t intervene it may simply fall, and this precious fragment of Scotland’s history will be lost.
“Most tower houses were modernised in the Georgian or Victorian periods, but Fairburn Tower’s unaltered form gives us a glimpse deep into Scotland’s past.”
Thomas Knowles, head of grants at HES, added: “The tower’s historical significance is underpinned in its A-listed status, which recognises its local and national importance as the former stronghold of Clan Mackenzie in the Highlands.”