TThe island of Foula lies some 15 miles off the Atlantic coast of Shetland. With 20 or more souls still living there, it can claim to be the most remote inhabited isle in the United Kingdom. It is only three miles long by less than two wide, and the whole of the western part is mountainous, with spectacular cliffs dropping to the sea – at over 1200ft, these cliffs at Kame are the highest in Britain. It has its own car ferry, just big enough to carry one car on the stern, and is also served by an eight-seater islander aircraft. There is no shop, no pub, just a Post Office and a school.
John Holbourn had to leave his beloved island for health reasons, and chose to settle in West Wiltshire. Here, he met Keith Turner, a member of the Bath and Camerton Archaeological Society with access to geophysics equipment. Helen Bradley had just completed a survey of Foula for her archaeology MA, and, as it happens, had recommended geophysical survey as the next step in exploring the island’s archaeology.
Two stone ‘eggs’
In May 2006, six members of the society flew north, blown by strong southerly winds, which brought wonderful weather: we were to lose only one afternoon to bad weather in ten days. Meantime, John had arrived on the island by car, laden to the roof with equipment, and only just enough space for his wheelchair.
The magnetometer survey of the Harrier Valley produced spectacular results, indicating both historic and prehistoric archaeology (the dividing line in Shetland is AD 800). While surveying the hilltop of Da Heights above the valley, one of our team thought that a group of protruding stones formed a circle, or nearly so. On our final day, the wind turned north to blow us home, but we did just manage to complete an EDM survey on the now bitterly cold hilltop. Only when we got home did we analyse the results. The stones formed two concentric rings.
These rings, however, were not circles but appeared to form an egg-shape. The long and short axes of the inner ring were 45m and 40m, while the axes of the outer ring were 70m and 60m. The long axis was directed to a bearing of 140 º – midwinter sunrise.
We were invited back in 2007 to explore these rings in more detail. Meantime, island resident Isobel Holbourn had climbed Da Heights in the pre-dawn gloom and cold of December to photograph the sunrise at midwinter. At 60 º north, this was after 9.00am, and by lunchtime, the low sun would be hidden behind the mountains.
We chose to return in June 2007 to get as near to midsummer as we could. The sun did set, but it remained light all night. However, we did find one disadvantage in timing: birds had begun to nest, restricting our access to some parts of the site. Unfortunately, we were unable to return in 2008 for a third season – when Shetland was actually the sunniest part of the UK!
We re-surveyed all the surface stones and used peat prodders to locate and survey the buried ones. In all, our survey included 290 stones. When these were plotted out, the inner ring was very clear and elliptical in shape, the outer ring less evident, although there were signs of some form of precinct, and stone rows approached this. The ring was not laid along the contours of the ridge, but was deliberately constructed aslant it, so the alignment on the winter solstice was clearly deliberate.
Our evaluation trenches were very revealing. One small stone had a gap under it and we could see more stones beneath. As Trench A was excavated, the ‘small stone’ was found to be 500mm tall and 300mm wide. It had been placed on a ring of stone footings above the bedrock, but it had toppled, as had the neighbouring stone. Trench C investigated a stone that was still upright. We found it sitting on similar footings, but it had been deliberately wedged into position.
This site is obviously not as spectacular as the magnificent rings on Orkney (CA 199), but it nonetheless represents quite a feat of building, and is in an even more remote place. Shetland does have other stone rings, but they are generally smaller than Da Heights.
The centre of the ring was almost devoid of stones, but not empty. A few years ago, the islanders had fortuitously placed a water-supply tank right in the middle of it! The pipeline trench to it had destroyed a portion of the ring in the south-west. The ring also contained a ‘planticrub’, a small stone structure to protect seedlings before they could be planted out. This was a rare design, being square rather than round, and it was unique on the island in that it had a name: Tamson’s Crub. There had long been talk of it having an earlier structure, and resistance survey in 2006 had shown strong signals close to it. Trench E confirmed that there were stone walls below it.
Paving, peat, and a potsherd
Trench B uncovered some of the interior, where resistance survey had shown higher readings. We came down on an area of paving flags, and found our only sherd of pottery and a few tiny fragments under 600mm of peat. It was not diagnostic, but we believe it to be prehistoric. We also took a number of peat samples for pollen analysis. Some of the deepest samples had traces of birch and willow. If this depth were the ground surface when the ring was built, then there were trees on this now-treeless landscape. The last time the climate was that mild was in the mid-Bronze Age.
Trench D confirmed that the outer ring had been built on similar footings to the inner ring. Trench F investigated the large Stone 42. Was it a fallen stone? Our work showed it was not fallen, but recumbent, and also carefully wedged in place. Recumbents are common in stone circles near Aberdeen, but the recumbents there are usually to the south-west and mark a lunar event. This recumbent was on the north-east.
Many rings with solar or lunar alignments point towards the setting sun. This is much easier to observe, as you do not have to get up in the cold and dark and wait for the rising, but on Foula that is impossible as the mountains mask all settings except to the very north-west (such as summer sunsets). We saw the midsummer sun set over the sea to the north of the mountains, directly opposite midwinter sunrise. Perhaps this was the real alignment. But our contour survey showed much better sightlines to the south-east, confirming the midwinter sunrise as the event to watch. Two of our number rose very early one morning to see the sun rise. As it did so, it slid up the side of Ronas Hill, Mainland Shetland’s highest point, well away to the north-east – and it rose over the recumbent Stone 42.
Watching the sun rise
So, we had a deliberately built structure of likely Bronze Age date, constructed aslant the ridge (which runs from east to west), and with solstice alignments. At the time of the equinox, the sun would rise directly along the ridge. Exact measurement of the equinox is difficult as sunrise is moving very fast then, but the concept of equinox is built into even the most primitive calendars, where it helps to indicate the start of the farming cycle.
Stone rings come under the general interpretation of ‘ritual’. Our structure was not sturdy enough to have been a livestock pound, and had no other obvious domestic interpretation, especially given its very exposed position. We therefore have to class it as ritual, as we seek to explain its function. There is so much more to discover about the purpose and the extent of the paving stones exposed within the ring in Trench B. What ceremony were they used for? Was the structure under the planticrub part of the ring, or a later installation?
Stone and timber rings are usually assumed to be the settings for ceremonies performed by priests in the presence of the general population, probably associated with birth or death, and with a rich associated symbolism of renewal. There is a cairn below, at Harrier, and a second only 50 metres away, but these are out of sight under the ridge.
Were the priests also astronomers? Was it the birth and death of the year that mattered? Seeing light grow after darkness? Interpretations of these monuments as solar or lunar event markers go back about 100 years to Norman Lockyer. The idea became popular following Gerald Hawkins’ book on Stonehenge in the 1960s, and then Alexander Thom’s books, which measured rings to high precision, and formulated special designs and a universal unit, the ‘Megalithic Yard’. The idea of the ‘astronomer-priest’ was much vaunted then, but since the 1980s, enthusiasm for these ideas has waned.
Our best interpretation is that the Da Heights ring had an astronomical function, though we do not claim the precision of layout that Alexander Thom claimed for his sites. It was enough to know that the sun had reached and passed the solstice; the exact timing – even assuming the sky was clear enough to observe – was secondary. It could be used to mark the main dates of the year, and these are important for farming and for fishing, especially in Shetland, so far north. We call that ‘practical’, not ‘ritual’!
Photos & images: Bath and Camerton Archaeological Society 2007
Bath and Camerton Archaeological Society
Visit the websites www.bacas.org.uk and www.foulaheritage.org.uk