By Rick Barton
At the end of our first week of excavation at the Swartigill Iron Age settlement, we are already starting to see some intriguing features within the structures, and tantalising traces of things to come.
Our team of excavators includes ORCA archaeologists, volunteer excavators and UHI Archaeology Institute undergraduate and postgraduate students. The covers and tyres placed over the site last year to protect it were taken off in record time – a testament to the enthusiasm of the students and their determination to start digging!
We were delighted to see how well preserved the site was from last year, with most areas looking just as though they had been left yesterday.
As eager as we all were to start work on the site, heavy rain slowed us down at the start of the week. But we were able to extend the trench to the south-west, so that we could start investigating Structure E – a small rectangular feature built from large stone blocks. One of our objectives for this year’s excavation is to discover the extent and form of this structure.
We know from our work last season that Structure E was built partially over an earlier building, Structure D.
Radiocarbon dates for Structure D tell us that it was occupied between the seventh to mid eighth century AD, which is towards the end of the Late Iron Age.
ORCA project officer Bobby Friel has been supervising and instructing UHI student excavators Steff Broadfoot and Nicola Thompson in the recording and excavation of the structure and these were joined by Aberdeen University archaeology student Fiona Piscreta.
Meanwhile, regular volunteers Deryck and Anthea Deane, have been helping to define the extent of this building to the south-west. As is so often the case, this structure is proving to be more complex than originally anticipated and we still have a lot of work to do before we can see its full shape and form.
To the east of Structure E, UHI Archaeology Institute masters student Sara Marinoni has been leading a team in Structure D.
At the end of the 2021 excavation, we encountered the beautifully curving northern wall face of this building and were only just starting to see traces of the southern arc of the wall. If we were anticipating that the architecture in the southern half of the building would be as simple to understand as the northern half, we would have been disappointed.
We are already seeing far more complexity in the arrangement of the walls in the southern arc of the structure, with traces of modifications and annexed features starting to emerge. Fortunately, we archaeologists thrive on the challenge of solving the puzzles present themselves while excavating these ancient sites, and Structure D is certainly exhibiting some interesting features.
Sara has been ably assisted by experienced local dig volunteer Rhona MacPherson and UHI Archaeology Institute student Caroline Still. They have been focused on the arduous, but ultimately rewarding, process of removing the alluvial soils that shrouds the archaeology across the site. They are now down to rubble layers that have been deliberately placed to backfill the structure.
To the north of Structure D, UHI PhD student Holly Young returned to the site this week and picked up where she left off last year – the careful excavation and sampling of floor surfaces in Structure B.
Radiocarbon dating of charred barley grain from samples recovered in 2021 tell us that this surface dated to between later ninth to early tenth century AD, the very end of the Late Iron Age period.
We believe this surface relates to re-use of the partially ruinous shell of the building as a makeshift shelter.
Holly has been instructing UHI Archaeology Institute undergraduate student Eve Clark in the process of sampling and recording this floor surface. During this process, they have revealed a hearth setting below it.
This new hearth defined by a semi-circular arrangement of edge-set stones and is by far the most formal hearth we have encountered on the site to date. It is early days in terms of our understanding of this feature, but it could represent a more consistent period of occupation in Structure B.
Directly to the west of Structure B, local community volunteer Rod Mann has been helping us to understand the deposits that overlay more structural remains. These layers contain large quantities of burnt stone.
This material is quite intriguing, since in a prehistoric context, people used hot stones in large quantities to heat water – a process commonly associated with Bronze Age sites that are aptly named “burnt mounds”.
There is no doubt that the burnt stone we are seeing at the Burn of Swartigill is related to Iron Age activity, but the question remains – what was the activity that produced so much burnt stone? That’s one of the questions we hope to answer as our investigation continues.
Last, but by no means least, Orkney College Archaeology NVQ student Travis Lowe has returned to continue our investigation of the eroding burn section. This year, Travis started by removing the remaining backfilled material from the Yarrows Heritage Trust original investigation in 2012.
We were unable to dig in this area in 2021, due to the presence of a beehive among the boulders! This year, however, the bees have moved on to pastures new, clearing the way for us investigate this part of the site.
Some of the earliest features on the site are present in this area, with radiocarbon dates for the layers being eroded in the burn dating to the mid fourth to second century BC – the Early to Middle Iron Age period.
If you would like to visit the excavation, the best times to come are between 8am and 5pm. We are on site from Monday, August 22 until Thursday, August 25.
After a short break, we’ll be back between Tuesday, August 30, and Thursday, September 8.
Our site open day is scheduled for Saturday, September 3.
That’s you all caught up with our progress so far. We have plenty of time left on site and will keep you up-to-date as we continue our investigation of this remarkable Iron Age settlement.