Callanish Stones still surprise

The beam of sunlight can be seen emanating from the base of the cave at Cnoc an Tursa. Photo: Ian McHardy
The beam of sunlight can be seen emanating from the base of the cave at Cnoc an Tursa. Photo: Ian McHardy

It may be centuries old, but the Callanish Stones site still throws up new observations about the beginnings of civilisation.

And last year, Hebridean archaeologist Ian McHardy made a discovery at Cnoc an Tursa – a rock formation beside the Callanish Stones site – which could reveal an ancient sun-powered calendar.

Located just outside the main Callanish Stones circle and consisting of five large stones that create a small cave, Cnoc an Tursa was the subject of an excavation by Gerald Coles, Edinburgh University, in the 1990s.

His findings uncovered a number of pits and post holes stretching out in straight lines from the cave; yet no real explanation was found as to what they might have been.

While waiting to meet fellow island archaeologist Margaret Curtis at the Stones one day last year, however, Ian witnessed an interesting interaction between the sun and Cnoc an Tursa.

“I’ve always wondered what Cnoc an Tursa was about, as although outside the main monument, it seems still significant,” said Ian.

“I was waiting for Margaret at midday on a bright, sunny day when I saw a shaft of light emanating out a good few metres from the base of the cave.

“As I watched, the shaft of light moved round like the hand of a clock as the sun travelled across the sky.”

Fascinated, Ian and Margaret studied the discovery over a period of time to find that the length of the light beam changed as the year progressed, getting shorter to longer from summer to winter.

“It means that the line of posts could have made the whole site act as a large annual sundial,” Ian expanded.

“Telling the time of year was fundamentally important to farmers in order to carry out essential tasks at the proper time of year, as well as for celebrating annual religious festivals.”

He continued: “And this idea also ties in with the solar and lunar alignments in the main monument, which could mean that the whole site acted as a clock and calendar.”

Dating to around 3,000BC, it is the importance of the Callanish site within the history and development of European mankind, illustrated by the possibility discovered at Cnoc an Tursa, which has prompted the Stornoway Gazette to campaign for the Stones to be awarded World Heritage Status.

And for Ian, who has been fascinated by the Callanish Stones since he first began working as an archaeologist in the Hebrides over 14 years ago, the monument deserves such protection.

He commented: “I believe that Callanish and Cnoc an Tursa are one of the earliest physical representations of our conception of time anywhere in the world, part of a fundamental stage in global human history.”

“This is why Callanish is a monument which should be seen as important to the whole human race – and so should have World Heritage Status.”

Do you think the Stones should be awarded World Heritage Status?

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