A team of archaeologists, led by Dr David Griffiths, of Oxford University, is working on and around the massive mound known as the Castle o’ Snusgar, to the north-east of the Bay o’ Skaill.
As reported in previous years, the aim of the project is to understand the development of the landscape in relation to the bay – the history of the way humans have adapted and used the landscape.
In particular, the archaeologists are interested in a series of six or seven mounds in the vicinity of the “Castle”.
This year, a trench was reopened on the castle mound to clarify how it formed over the centuries. The result has been, according to Dr Griffiths, ” an excavation in beautiful [ly preserved] stratigraphy.”
Like slicing into a cake, the trench shows the various layers that go to make up the mounds – including man-made midden deposits, soil and episodes of wind-blown sand – one of Skaill’s most notorious problems.
Given the make-up of the sand-layer, Dr Griffiths suggests that at the core of the Snusgar mound, there is possible a prehistoric structure.
This, he thinks, would have acted as a sand-trap, forming a low mound that was then built upon by the later settlers.
Specialist examination of environmental elements from the soil will allow the various phases to be dated. And these, together with ongoing scans by Orkney College’s geophysics unit, are gradually building up a picture of the area.
Sixty metres to the east of Snusgar, trenches on the top of another mound have revealed more of a stone structure first exposed last year.
Clearly visible now are a series of stone walls, what appears to be a flagged corridor, and stone orthostats, which presumably acted as room dividers.
Although it is too early to say much about this structure, Dr Griffiths thinks it is probably Viking age, which two separate phases of construction visible.
It was from this structure that one of the dig’s most spectacular finds to date was unearthed.
A Viking crutch-headed pin in immaculate condition turned up in the trench, along with seven pieces of steatite – a stone used by the Norse for making pots etc, and a tiny blue glass bead.
The undamaged pin, said Dr Griffiths, appears to be of a type from the 10th century, which would have been made in Dublin.
The Snusgar excavation was supported by Historic Scotland and Oxford University.