Imagine a massive jigsaw puzzle.
But this is no ordinary puzzle. Not only is there no picture on the box lid, but every time a piece is slotted into place, the puzzle gets bigger and more complex.
And that is the situation with the Ness of Brodgar.
As you read this, this summer’s excavation work at the Neolithic site, in Stenness, will be in its final few days. But once again, the enigmatic Stone Age settlement has left the archaeologists with as many questions as answers.
But after six weeks of digging, and with over 5,000 visitors to the excavation site, it can quite safely be said that 2010 has been a groundbreaking season.
Aside from northern Europe’s first painted stones and the Neolithic roof slates, the site has continued to produce decorated pottery and incised artwork, not to mention finds such as a whale’s tooth and whalebone macehead, from Structure Eight. And yet another large building — Structure Twelve.
Leading the excavation in this, the sixth year, was Nick Card, from the Orkney Research Centre for Archaeology (ORCA) .
He said: “Every year, the site never fails to astound us. Its not just the scale of the structures, the beauty of the stonework, the amazing survival of Neolithic walls, the exquisite finds, the artwork etc., but really every aspect of the site — this site is truly unique and, as ever, one feels it is a great privilege to be working here”
Digging resumed on July 19, and one of the earliest theories to fall by the wayside was that an extensive geophysics anomaly could be the remnants of a giant prehistoric structure.
Nick explained: “Initially, I wondered whether we had another section of our existing Structure Eight, possibly over 35 metres long. But once we got down to the archaeology, it became clear that what we actually had was a completely separate building.
” Structure Twelve, as it was christened, turned out to be yet another hybrid building, sharing architectural elements with the existing Structures One and Eight. The construction of its outer wall reflects Structure One, but inside, the tapered piers are similar to Structure Eight, though on a larger scale.
“The walls define a truly monumental structure, over 15 metres long and over ten metres wide, with rounded ends, straight side walls and a series of internal dividing piers,” said Nick.
“As with Structure One, there seems to have been several phases of alterations, with an north-facing entrance being narrowed; a complex ‘porch’ type arrangement added; and sections of wall being rebuilt.
“And like all the other structures on site, the stonework is something to behold — beautifully built walls, with tapered piers creating recesses along each side wall, and the possibility of smaller, perhaps corbelled, recesses at either end of the side walls.”
Outside Structure Twelve, a trench opened against its outer wall face, revealed what appears to be another wall face, about 50cm outside of the building’s outer revetment. Is there another adjacent structure? Or is Structure Twelve, like its neighbour, Structure Ten surrounded by a wall?
The answer to this will have to wait until next season.
Inside Structure Ten — the “Stone Age cathedral” — work concentrated on the inner chamber — in particular its central hearth and the “dresser” directly opposite the entrance.
Measuring six metres across, the inner chamber is a slightly larger “copy” of Maeshowe’s central chamber and, last year, was found to contain the remains of a Neolithic stone dresser — but where these are generally found built against the walls — at Skara Brae, for example — in Structure Ten it was free-standing and more elaborate than those found in Orkney to date.
Nick said: “By the time we finished excavating the dresser, every indication was that it was originally freestanding, with a narrow space behind it.
“A large ‘dressed’ slab, shaped and smoothed by surface pecking, lay across the front of it and this was also reinterpreted as a fallen pillar that once supported the right hand side of fixture, matching the central support.
“Although this now appears as a rather precarious looking piece of stone furniture, it must have been kept stable by the weight of the presumed stone shelves that the pillars supported. Most of it has collapsed, with only segments surviving of the back and side walls and the central support.
“As well as red sandstone being used for the central support, naturally coloured yellow sandstone was also used, presumably for decorative purposes, and several of the stones were also enhanced and shaped with extensive areas of pecking noted on their faces.”
Its position, and the east-west construction of Structure Ten, suggests that the building was linked to the rising sun at the spring and autumn equinoxes — the midpoint between the winter and summer solstices; a “time between times”.
Nick added: “Imagine, the large cup and ring stone, the so-called ‘Brodgar Eye’ discovered by the dresser last year, perhaps being set into it.
“What a splendid sight this must have presented, as the light from the rising sun entered the inner chamber to illuminate this ornately decorated fixture. It also begs the question, does the circular decoration represent the sun?”
This year’s discovery of a central hearth was a surprise, though not entirely unexpected.
Measuring 1.2 metres across, it contained deposits, rich in animal bone, as well as a large decorated stone and an inverted cow skull. This is reminiscent of the discoveries at the Links of Noltland, where over 30 cattle skulls were incorporated into the wall core of an early Neolithic house.
“Astone block was decorated with several circular ‘cup marks’ and had been carefully placed in the centre of the hearth — perhaps marking its last use,” said Nick.
“The upturned cow skull was just to the east of this decorated stone, near the inner edge of the hearth. The arrangement of cattle skulls in particular places is an often-recorded feature of prehistoric sites, perhaps exemplified by the recent discoveries at the Links of Noltland.
“It is tempting to think of the inverted skull as representing the final meal prepared in Structure Ten and, if this was the case, is it related to the huge deposit of cattle bone, mainly cattle tibia, in the upper fills of the building’s surrounding ‘passageway’? These do seem to indicate a massive feasting event when this building was ‘decommissioned’.”
Was the upside-down skull a symbol of death and completion?
Research suggests that cattle skulls may have been used in prehistoric funeral rites similar to those still observed among some groups living on the island of Madagascar. These Madagascans let their dead decompose in a temporary grave and then, at an elaborate feast, deposit the bones in a permanent tomb.
The skulls of the cattle slaughtered for the feast are placed on, or near, the grave. Because the skulls are considered emblems of virility and power, mourners gather large numbers of them for the tombs of important people.
Professor Mike Parker Pearson, himself an expert of Madagascan funerary rites, was visiting the Ness of Brodgar last week.
He agreed that the inverted skull could represent a ritual closure of the building, but added: “I think for this idea to be more convincing, we’d need to find more situations where that is happening. It’s early days for Nick. There’s an awful lot more digging to do before we see more floor deposits.
“The sense of closing down the house formally is something we’re very familiar with down in Durrington Walls. What they did there is dig a pit through the floor and then all their feasting debris, from, what is presumably, a kind of last supper, went into that. And with that the house is decommissioned.
“So the cow skull and stone is maybe a different regional tradition of closing here.”
Another interesting feature of the hearth is that half of it appears to have been deliberately removed. Were the missing hearthstones transferred to a new building to begin its life? This reflects the previous discovery, by Dr Colin Richards, that a hearth was transferred from the Barnhouse Settlement to the centre of the Standing Stones of Stenness.
Outside Structure Ten, a recess, adjacent to the stump of the standing stone revealed last year, was also found to contain a deposit of animal bone – buried under the floor.
Meanwhile, in the outer “courtyard” annex to Structure Ten, several crucial discoveries regarding the sequence of events became clearer. Although no obvious break in the external wall face could be detected to show that the annex was a later addition to the main body of Structure Ten, it had always seemed likely that this was the case. Below the deposits in the small side cell, it became clear that paving disappeared under the annex walls.
The walls, however, do not sit directly on the paving but on a thin, uneven deposit, just above it.
According to Nick, this seems to indicate that the paving predates the annex and perhaps indicates an original continuation of the outer, paved passageway that seems to surround Structure Ten.
He said: “This paving is also under the rather slap-dash walling that defines inner wall face of the annex, so, as predicted, it seems that the annex/forecourt was a later addition. We have still to determine whether the standing stone stump predates the annex or was erected at the same time as the rest of the annex was constructed.”
Another curious feature discovered just outside the annex’s side recess was a stone drain. Its relationship to the annex is still unclear, but the archaeologists suspect it runs into a drain that may underlie the paving surrounding Structure Ten.
However, there does seem to be a gentle curve in its line that seems to lead it towards the stump of the standing stone — a fact that led to much speculation on site.
The site continued to produce a mass of decorated stone.
Structure Ten, for example, produced a large block of stone featuring well-defined cup marks.
This stone may well form one side of the long anticipated entrance into Structure Ten — but if so, would seem to place the entrance slightly off centre; not quite what was expected.
Work in Structure Twelve uncovered a beautiful example of geometric artwork to add to the collection.
Last week, a small thin stone slab, decorated with two finely incised squares – one of which was filled with cross-hatched lines forming what was described as “a slightly compressed miniature chess board.”
A ‘lesser’ wall in name only
Work resumed on the “Lesser Wall of Brodgar” this summer and by the time its base was reached it was ‘lesser’ in name only.
A trench in the garden of the adjoining property, Lochview, south-east of the main trench, revealed the outer face of the wall, which has survived to 1.7 metres, with a flagstone pathway along its base. The incredibly masonry of the wall’s outer face had to be seen to be believed.
“The sheer beauty of the stonework leaves everyone who has seen it with a sense of awe and wonder,” said Nick.
“What a sight would have greeted the Neolithic people as they approached the Ness from the Stones of Stenness — they too must a felt the same sense of wonderment we feel today.”
But there was more.
Although it had been expected that the paving at the foot of the wall would be sitting on boulder clay or bedrock – to provide a stable foundation, as in the case of the “Great Wall of Brodgar” — it appears the wall was built on top of older archaeology.
Nick explained: “When a section of the paving was removed, it revealed rich midden deposits under the paving and a wall line that seem to extend below the Lesser Wall. So we have structures, and occupations, that predates the Lesser Wall, on which it was built.
“This came as something of a surprise since there was no obvious subsidence associated with the Lesser Wall, unlike other structures on site that have been built over earlier structures — it seems as straight and vertical today as the day it was built!
“To have discovered earlier structures on site should have come as no surprise, as both the original test pitting and some of the geophysical surveys indicated a huge depth of archaeology on site. How this revelation fits into the overall site interpretation we have yet to fully fathom.”
Structure Eight and the slate roof
In the years since Skara Brae re-emerged from the sand, one of the most commonly asked questions has been how were these Neolithic structures roofed.
Because nothing survived of Skara Brae’s roof structures, we must assume that they were made of a perishable, organic material — whalebone or driftwood beams supporting a roof of turf, skins, thatched seaweed or straw.
But out on the Ness of Brodgar, the archaeologists at the ongoing Orkney Research Centre for Archaeology (ORCA) excavations have found Orkney’s first real evidence of a Neolithic roof.
In most reconstructions of prehistoric buildings, you’ll often see hotch-potched arrangements of turf, animal skins or perhaps thatch. But on the Ness, the Stone Age builders used stone slates for at least one of their buildings — the remains of which have been uncovered within the side recesses along the interior walls of Structure Eight.
Site director Nick Card explained: “In the Structure Eight recesses, when we removed the upper layers of rubble, we found large, flat stone slabs, most of which would appear to be a standard thickness.
“Most of these thin slabs have been carefully shaped, with the edges trimmed to form regular, rectangular ‘slates.’”
Are we seeing the first evidence for a “standard” roofing system? Perhaps not for structures such as those at Skara Brae — in Structure Eight the excavators only found evidence for stone slates being used in the side recesses.
Nick said: “We may find other evidence as we dig, but perhaps this technique was only used to roof the side recesses as the limited span across these spaces would have made it quite easy.”
With no evidence of post holes inside the structure, it seems likely that a wooden framework was secured to the top of the building’s walls, and the slates attached to it.
Nick added: “Mixed in with the ‘slates’ are also some deposits of clay – was this used to calk the spaces between the slates to stop water ingress? Or possibly to bed the slates down on so as to achieve a more regular profile for the roof?”
Every “slate” is being carefully removed in sequence, numbered, measured and recorded so that the experts can not only piece together how they were used but also the way that the roof collapsed.
“Of course, it may be that the roofing was deliberately demolished – an act of ritual closure found at other Neolithic sites in Orkney,” Nick said.
Continued removal of rubble and collapse in the central area of Structure Eight revealed more roofing slates.
“We are asking ourselves now whether this means the whole of Structure Eight was slated and not just the recesses as we first thought,” said Nick.
“In addition, the odd slate was also being discovered in Structure One – so could other structures on the site been likewise roofed?”
Back when it was first fully uncovered, in July 2007, parallels were soon drawn between Structure One and House Two, at the nearby Barnhouse Settlement.
The Barnhouse link was further reinforced this summer, with the discovery of a third entrance into Structure One, and a suspected hearth built into its floor.
This third entrance, on the eastern side of the building, led into the primary phase of the building, when, in plan, it resembled Barnhouse’s House Two.
The latest entrance added to the two entrances already revealed at either side of the building – an unusual feature which has raised questions as to how the building was use. If the third entrance did feature a hearth, and not a series of threshold stones, the feature is most likely symbolic.
At Barnhouse’s Structure Eight, a hearth was built into the floor and flanked by two standing stones. Because it was paved over, its inclusion had no practical purpose so was interpreted as some form of ritual purification that took place before any individual was permitted to enter the inner chamber. In addition, this year’s excavations revealed a paved passage between Structure One and the earlier phase of Structure Seven.
Although most of the buildings on the Ness, like Barnhouse, were free-standing, it has been suggested that there were enclosed passages joining some of the buildings, creating a series of covered walkways.
The search for further evidence of this will have to wait until next year.
The 2010 Ness of Brodgar excavations were supported by Orkney Islands Council, Russel Trust, Robert Kiln Trust, Orkney Archaeology Society, Historic Scotland, LEADER European Fund and Orkney College UHI.