AT their simplest, the cairns which dot the countryside of Scotland are just piles of stones.

But in our history and culture, they are often hugely important as they were erected to mark the events of a community’s life or to act as tombs.

I should perhaps have included them in my recent series on Scotland’s built heritage but always intended to treat them separately, as cairns have always been of special interest to me – and clearly to many other people, as my column on Clyde-Carlingford cairns last week provoked a considerable electronic postbag.

Peter McFarlane emailed me to say: “I enjoyed your piece on the Clyde-Carlingford cairns. I’ve spent a lot of time on the west coast for work and play and a recent trip round Kintyre away from the big hills gave me some new insight into history both local and linked to our near neighbours. Your piece reinforces this with more exploring now to be done.”

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I’m glad to hear that, Peter – one of the reasons I write this column is to hopefully inspire readers to do their own research into the utterly fascinating subject that is Scottish history. Today I will tell the story of the Clava Cairns and hope that National readers will be encouraged to find out more about these Scottish phenomena.

Peter added: “One cairn that has long intrigued me since Tom Weir featured it many moons ago is Clach na Briton above Glen Falloch. So little written about it but so grand and accessible, too, with a little effort. Any insights that I’ve missed on that? Be nice to know it was a part of the wider story somehow.”

It’s a cairn that has fascinated me, too. I’ve seen its name spelled as Clach na Briton or Clach nam Breatann (below) but in English both versions translate as “Stone of the Britons”. It is an impressive construction, possibly a naturally occurring boulder outcrop topped by a large slab placed by human hands.

The National:

Most experts agree it is a boundary stone marking the division between Dalriada, the kingdom of the Scots, and the Brythonic kingdom of Strathclyde which had Dumbarton as its capital.

Clach na Briton is therefore much later than the Neolithic or New Stone Age cairns I wrote about last week, but reader Jim Rideout emailed me to point out that recent research has given us new ideas about the Bronze Age, which followed the Stone Age. He wrote: “I’d like to point out that there is no actual connection between the megalithic monuments you refer to and the ‘Celtic’ period in Scotland and Ireland. Since the days when the Clyde-Carlingford ‘culture’ was named and commented on there have been major changes in the understanding of the period.

“These megaliths were communal spaces, for ceremony and burial, in the Neolithic period. Burials of individuals in cists (often under cairns or barrows) were introduced in the Bronze Age. In the early stages of the Bronze Age there was an almost complete replacement in the population (more than 90%) as well as a cultural change.

“The communal monuments like long cairns, henges, stone circles and cursuses were replaced by the socially stratified Bronze Age monuments. Individual burials, some with high-status grave goods (see the Amesbury Archer, who is known to have been non-native).

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“Genetic studies have shown that the Neolithic populations in Britain and Europe were quite different from the Bronze Age populations, the former originating in farming communities in the Near East, the latter from Steppe-dwellers who gradually spread their genes across Europe, Iran and India.

“The current accepted theory is that the source of the Bronze Age culture, and all Indo-European languages, was the Yamnaya Culture of the Pontic Steppe (Ukraine and Russia north of the Black and Caspian Seas). That, however, doesn’t negate your approach to close communication between Northern Ireland and western Scotland. Cultural links across the water have been going on since at least the Neolithic period.”

Mea culpa and it’s useful to get a timely reminder to keep my researches up to date! In that regard I will be responding next week to a reader’s request for information on the Beaker People in Scotland – can you tell I’m enjoying my romp through prehistoric Scotland?

She wrote to ask: “I have always understood the Beaker People to be a purely English phenomenon but I recently discovered they were here in Scotland, too. Can you enlighten me?”

I sincerely hope I can, but have plenty of research to complete before I write next week’s column.

Meanwhile, I turn to the subject of the Clava Cairns, which gained a new height of fame when they became associated with Outlander, Diana Gabaldon’s creation, which has done more than any other book/TV series to promote Scottish history.

The National:

The look of her time travel portal Craigh na Dun is based on the standing stones at Callanish on Lewis, but many Outlander fans think she was inspired by the Clava Cairns, given they are so close to Culloden. Craigh na Dun is entirely fictional, I should point out, and the “stones” are apparently made of fibreglass, so don’t go looking for it.

Instead you can visit real history in the shape of the Clava Cairns, of which there are almost 50 in total, all located in the valley of the River Nairn. The name Clava comes from the largest and most important collection of cairns at Clava some six miles east of Inverness and only just over a mile from the battlefield of Culloden.

If you are visiting what I have often termed the saddest place in Scotland, it is worth going that extra mile from the battlefield to see the well-preserved and well-maintained cairns. Just follow the tourist signs – and you will also see the spectacular Culloden Viaduct (the longest masonry viaduct in Scotland), which I mentioned in my recent series on transport heritage.

Today I will concentrate on the three main cairns on the sites at Balnaruan of Clava and Milton of Clava, as it is these monuments which gives the class name to this type of cairn.

The earliest Clava cairns were long thought to have been created in the Neolithic period, the “New Stone Age.” It was only in the mid-1990s that Professor Richard Bradley led a comprehensive excavation and examination of the Balnaruan site.

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His findings were surprising, but very definite: the cairns did not date from the Stone Age but from the early Bronze Age – which is a millennium or more later than originally thought.

Now in the care of Historic Environment Scotland (HES), these 2000-year-old cairns are visited by more than 100,000 people annually. They are set in a stunning location within a small wood. According to HES, Balnuaran of Clava comprises two passage graves, a kerb ring cairn, a central ring cairn and standing stones. Milton of Clava, a short distance to the south-west, includes the remains of another cairn and possible standing stones.

HES states on its website: “The Clava Cairns comprise part of one, if not two, Bronze Age cemeteries. This landscape was an important place for ritual and burial activities in the Bronze Age. Later burials at the site suggest continued significance for over a millennium.

“The three well-preserved cairns at Balnuaran each have a central chamber. But while the two outer cairns have entrance passages, the chamber of the central one is enclosed. Each cairn is surrounded by a ring of standing stones. Many of the stones used to construct the cairns have cup marks on them – these may have been reused from another place, perhaps an earlier sacred site.”

Since there is nothing in writing to describe how and why they were built, archaeologists have had to surmise facts from the cairns themselves. When you realise the significance of the seasons of the year to people whose lives depended on agriculture, it is hard to conclude otherwise than that the cairns provided a valuable service as a sort of giant sundial.

HES continues: “The cemetery at Clava suggests that midwinter was an important time of year for the society who built them. The three prominent cairns form a line running north-east to south-west. The passages of the two cairns are also aligned towards the south-west, suggesting that the builders had their eyes on the midwinter sunset.

“The standing stones also suggest a focus on the midwinter sunset – they are graded in height with the tallest facing the setting sun in the south-west.

“Considerable thought must have gone into the planning and construction of the graves. The midwinter solstice would have marked an important turning point in the year – many similar monuments across the British Isles have a similar alignment with movements of the midwinter sun. Such sites can tell us about beliefs of past societies and how they understood their world.”

Bradley’s research confirmed that the cairns were used in different millennia and a newer cairn, known as the kerb cairn, was erected at that time. HES states: “Some 1000 years later, the cemetery was reused – new burials were placed in existing cairns, and three smaller monuments, including the kerb cairn, were built.”

At nearby Milton of Clava, the remaining outline of a Christian chapel can be seen on the ground. Legend has it that the chapel was erected as the burial place of King Brude (or Bridei), the king of the Picts who was converted to Christianity by St Columba.

In researching this column I was aided yet again by that excellent website Electric Scotland, which features an article based on a talk by that great artist and educator George Bain (1881-1968). Drawing on earlier work by the Inverness antiquarian James Fraser, Bain – who will get a column to himself one Tuesday soon – said the finding of an urn for holding ashes was key to understanding the Clava Cairns.

Bain said: “In the first place, we have here evidence of burial by burning the bodies. Cremation in our day is urged upon sanitary grounds, but we know from history that it was practised in ancient times from religious beliefs – a rite, moreover, which was frequently confined to the higher classes as a special mark of honour.

“In the second place, we have clear evidence that the people who built these cairns were no rude barbarians. They had, it is apparent, some knowledge of the potter’s art, as is shown in the manufacture of the urn. They had acquired some little skill in masonry, and could design and execute a vaulted chamber and dome roof.

“We find also that the concentric circle is familiar to them. Further, we see that they were capable of taking accurate measurements – if not to mathematical exactitude, at least to remarkable precision. They knew something of the cardinal points of astronomy or of direction, as is shown by the similarity of the two built entrances and the position of the taller pillars in the outer row.

“Now, let me ask, why is there the expenditure of all this skill, labour, and knowledge? Unquestionably, it points, I think, to its being all done in honour of the ashes enclosed in the heart of the cairn – to the remains enshrined in the urn – like something very precious in a costly casket … “The evidence considered in detail, and the design of the structure viewed as a whole, lead irresistibly to the conclusion that we have embodied here the one great idea of reverence for, and exaltation of, the dead, passing, it may be, into its higher phase of ancestral worship.

“They are the tombs of ‘the mighty dead of a past age’ – the burial places, it may be, of their kings or chiefs. They have been raised in honour of a special class. That is one great fact regarding them of which there is good proof.”

Whoever built them – and Bain is sure it was the “Northern Picts” – the Clava Cairns are tangible reminders of our ancestors.