Excavation Iron Age The Cairns

The Cairns dig diary – day one

We're back! We have been largely absent from site for far too long, but this year we are finally returning in strength!
The Broch interior- to be a major focus of work this year. (ORCA)
The broch interior- to be a major focus of work this year. (ORCA)

Plans for the 2023 season

Hello everyone and welcome back to our regular blog for The Cairns excavation project!

Due to the hiatus of two years of Covid-19 lockdown and my own ill-health last year (just as we were about to commence the fieldwork), we have been largely absent from site for far too long, but this year we are finally returning in strength!

Today was spent finishing the removal of all the protective covers and tyres and, by the end of the day, we have accomplished a lot – thanks to our dedicated team of professionals, students, and volunteers. And thanks also to the beautiful sunny weather, we’re ready to commence proper excavation tomorrow.

Let’s catch up a little on last year and look forward to what we’re going to focus on this year in the excavations.

Sterling work was done in the summer of 2022 – I want to thank my colleagues Kevin, Bobby, and Rick, and the group of UHI Archaeology students, for keeping the project going while I was absent!

Although smaller in scale than we had planned, the 2022 work concentrated on important buildings (Structures G and N) on the northern edge of the main trench.

This summer, we return at last to the broch that lies at the centre of the site, and to other important areas.

Here are our plans for the 2023 season:

The broch

Site tour near the broch first thing this morning. (ORCA)
Site tour near the broch first thing this morning. (ORCA)

We are going to concentrate our excavation efforts on the broch interior, excavating floors and occupation deposits.

The broch interior has been very rich in past seasons with a well-preserved series of floors and deposits containing animal bone, environmental material, and some remarkable finds.

Beautiful glass beads and metal jewellery items are some of the more memorable artefacts to have come from the broch.

The Cairns bowl after conservation.
The Cairns bowl after conservation.

We should also remember that the astonishing wooden bowl – the “Cairns Cog” – came from the broch interior, down in the “well“, where we found remarkable strands of preserved human hair!

Overall, our research intends to produce one of the most complete excavations of a broch occupation ever undertaken. To that end, we excavate on a grid to keep spatial control over the findings and we recover 100 per cent of all the soft soil deposits in sample tubs. These are then sieved for environmental information, micro-artefacts and other content.

Cairns broch interior plan.
The broch interior.

We’ve spent a lot of time excavating the broch occupation already and, in certain zones of the interior, have recovered evidence of long periods of occupation and recurrent renewal.

In the “West Room”, for example, we’ve revealed three successive superimposed floors with slab surfaces and hearths. Each stone floor was capped by a set of occupation deposits before the next solid floor renewal took place.These cycles of occupation seem to attest to the longevity and continuity of occupation in the broch.

We think we’ve reached the earliest surviving cycle of occupation in the West Room, but elsewhere, in other areas/rooms, we’ve a long way to go before reaching similarly early moments.

The essence of our work in the broch this year, then, is to broaden out and excavate as much of the deposits in other parts of the broch interior to the same extent.

To give you a sense of why that’s important, we can compare the West Room to the South and South-East Rooms.

So far, we’ve found that the West Room is rich in certain types of animal bone – especially red deer, cattle and young pig – while the South and South-East rooms are rich in seal, fish, shellfish, and whalebone.

The West Room is rich in pottery, metal objects and glass beads while the South and South-East rooms are rich in stone and bone tools.

It’s only through the detailed excavation and recovery of deposits, artefacts and items from a range of different areas of the broch, that the distinctions between these inventories and activities becomes clear. These contrasts probably indicate the different sorts of activities under way in these rooms during the Iron Age and, quite possibly, different identities within the household.

This season we’ll excavate more of the broch occupation deposits than ever before.

Village people!

Structure O in the foreground during the process of uncovering today. (ORCA)

We intend to investigate more of the broch village this season, which is important because we still don’t know as much about them as we would like.

Although there’s no doubt that Iron Age villages can be contemporary with brochs, it’s not clear whether some villages were built at the same time as the broch, or whether village buildings developed more organically, a while after its establishment.

We also want to know more about the social relationship between the inhabitants of the broch and those of the village buildings.

Plan of The Cairns Excavation

In Scottish Iron Age studies, the consensus has been that the brochs represented the residences of high-status families who held economic and political power over the village dwellers.

An alternative scenario is that the entire community was on a more equal footing and the broch was a communal structure, where food was stored and feasting was undertaken – a symbol of the community’s solidarity and a projection of its power directed beyond the settlement to the outside world.

It may be that a more subtle version of events, combining elements of both of these models, is tenable.

Discussion in Structure O this morning. (ORCA)
Discussion in Structure O this morning. (ORCA)

So, the second area we’re going to concentrate our efforts on is Structure O, which lies just outside, and east of, the broch entrance.

Presently, as indicated by our radiocarbon dating, Structure O appears to be a sub-rectangular building, contemporary with the broch. It has well-built, free-standing walls and, we suspect, was a substantial village house of the Middle Iron Age.

The full outline of this building has eluded us so far because of the structural complexity at The Cairns.

Structure O.

In 2019, as we attempted to reveal the whole footprint of the Structure O, we found that it was partially overlain by a late wall and slab floor. We think the late wall is part of a series of revetments, intriguing tiers of walling built around the eastern end of the broch ruins (the “broch mound”) during the 5th century AD.

Before proceeding to reveal the whole of Structure O, and its detailed relationship with the broch, we have to record and excavate this late episode.

Return of ‘the Elder’

The third area we intend to focus on this season lies just outside the broch entrance, between the broch and Structure O.

This area is where we previously discovered the remarkable “Elder assemblage” – a deposit comprising a huge bone vessel carved from the vertebra of a fin whale. The vessel contained two newborn lambs and a human jawbone.

The whalebone vessel, which contained the human mandible, with the deer antlers and saddle quern outside the broch entrance.
The way it was – the “Elder Assemblage’ in 2016. The whalebone vessel, which contained the human mandible, with the deer antlers and saddle quern outside the broch entrance, will be another scene of excavation this year. (ORCA)

The person represented by this jawbone has been nicknamed “The Elder” due to her apparent long lifespan. Her remains, and the other items, were placed directly against the broch outer wall-face just as the structure was coming to an end.

We suggest that was part of an even more extensive series of deposits that formed a highly elaborate process of closing-down the broch.

This saw the placement of groups of artefacts, including the wooden bowl within the well, multiple animal carcasses placed across the last broch floors and even in the rubble infill of the broch. These were offerings, perhaps, to secure a good outcome and an auspicious aftermath for the generation who ended the broch, around the year AD200.

The “Elder assemblage” is the most complex element of this extensive act of closure of the broch.

This season, we want to further investigate the context of the “Elder assemblage”.

We think there is considerable animal bone and shell midden still present in the vicinity, which could represent food remains emanating directly from the broch itself. This could give us highly important information for the lifestyle and economy of the broch household.

At the same time, while we don’t expect to find any more human remains, there may yet be further items of a deliberately deposited nature – additional components of the special deposit.

Final thoughts

Overall, then, the three main areas of attention this season represent a continuous zone of investigation running across our main trench from west to east.

We will undertake smaller scale explorations of a few other areas and features, such as Structure C, a Late Iron Age complex built into the north-eastern broch wall. In the main, however, we’ll concentrate our intensive focus on the broch and the heart of the site.

We’ll keep you posted on how we get on…

Martin Carruthers
Site Director, The Cairns