Setting boundaries

The ‘Great’ and ‘Lesser’ Walls of Brodgar

Northern Boundary Wall representation
“Built on a monumental scale […] these walls created impressive facades that would have been encountered by people moving towards the site from the Bridge of Brodgar to the south-east, and from the undulating ground to the north-west. Working with the waters on either side, they may have formed a coherent enclosing boundary for part of the sequence.”
Nick Card and Mark Edmonds. Setting Boundaries
The Ness of Brodgar: As it Stands
. (2020)

For part of its life, the Ness of Brodgar complex was bounded by two large, stone walls – both of which ran the width of the peninsula and visibly separated the buildings within from the world outside.

The northern boundary wall

Geophysical surveys had indicated an immense feature – with an entrance – running across the Ness of Brodgar to the north-west of the excavation site.

A second, smaller, anomaly did the same to the south-east.

Interpretation of the 2013 gradiometer survey results.  (📷 ORCA)
Interpretation of the 2013 gradiometer survey results. (📷 ORCA)

The first physical encounter with the northern boundary wall – subsequently dubbed the “Great Wall of Brodgar” – was in Trench J, where a corner section of the four-metre-wide (13ft) construction was revealed in 2005.

To put the its scale into context, Hadrian’s Wall was originally intended to be three metres wide but reduced to 2.4 metres.

Two trenches, M and N, dug to the south-west of Trench J, confirmed the “Great Wall” continued across the width of the peninsula, surviving to a height of 65 centimetres in places.

2023: Trench J, with the northern boundary wall pictured top, curving around Structure Five. (📷 Tom O'Brien)
2023: Trench J, with the northern boundary wall pictured top, curving around Structure Five. (📷 Tom O’Brien)

Traces of a two-metre-wide ditch, around 60cm deep, that ran parallel to the outer wall face were also found in Trench M, as well as evidence that a section of the wall around an apparent entrance was widened to six metres.

Whether this extension related solely to enhancing the entrance remains to be seen.

It may be that the extra masonry was added after the wall had been partially dismantled – perhaps an attempt to monumentalise the original construction?

Excavation has confirmed that the “Great Wall” was well built, with a row of massive boulders forming its core. Inner and outer wall faces were added either side of this and the area between filled with smaller waterworn cobbles.

There is a notable difference between the wall’s inner and outer faces.

The exterior – the side viewed from outside the Ness complex – saw carefully selected, large, rectangular sandstone blocks used at its base with regular courses of quarried stone above.

This is in sharp contrast to the inner wall face, which featured irregularly coursed stone – the building material of random size and, occasionally, irregularly shaped.

Interestingly, it is also markedly different what we see with the buildings, where the outer masonry is inferior to that found in the interior.

The role of the wall

The 'Great Wall of Brodgar' in 2021, curving around Structure Five's northern end (left) before coming to an abrupt stop. (Sigurd Towrie)
2021: The ‘Great Wall of Brodgar’ curving around Structure Five’s northern end (left) before coming to an abrupt stop. (📷 Sigurd Towrie)

People in the Neolithic seem to have been obsessed with demarcating and enclosing space – the most obvious examples being the ditches, banks, walls and standing stones we see around monuments such as Maeshowe, the Ring of Brodgar and Stones of Stenness.

2008: The wall and Structure Five emerging from Trench J.
2008: The wall and Structure Five emerging from Trench J.

Boundaries controlled access.

They not only kept people out but, in some cases, perhaps kept “something” in – enclosing and containing an area.  

There is no doubt that boundaries were clearly important elements in the Neolithic. But the “Great Wall” took this to a new level.


Based on the current evidence it seems unlikely that the northern boundary wall was built for defence. For one thing, you do not need a four-metre-wide wall to provide an adequate defensive structure.

But more telling is the simple fact that the wall stops dead after curving around the north-eastern end of Structure Five.

There is a major flaw in your defensive plans if your would-be attackers could just stroll around the corner.

Instead, the boundary walls – like the buildings they contained – made a highly visual statement.

They not only marked the boundaries of an area of special significance but separated it from the “outside world”.

Great Wall of Brodgar
2019: The exposed northern corner of the ‘Great Wall’ curving around Structure Five before coming to an abrupt stop. (📷 Scott Pike)

The “Great Wall” did this with style.

The imposing construction, monumental entrance and ditches would have dominated the Ness of Brodgar from all directions, its monumental scale making a stark and conspicuous statement:  This is our place. We can, and have, built this.

The effort and time that went into the wall’s construction would be clear to all who viewed it, reinforcing the influence, status and power of those involved in the activities beyond it.

As we have seen, the stonework on the northern wall’s outer face was much finer than that of the inner.

Although we cannot say for sure, it, like the buildings, was perhaps embellished with decorated and coloured stone.

This strongly suggests it was meant to be seen from the north-west and by those outside, or approaching, the complex.

Defining a ‘no-go’ area?

The “Great Wall” appears to have been more than an imposing barrier to the living.

In 2004, geophysical surveys of the Ness of Brodgar isthmus revealed a distinct lack of archaeological activity in a large area surrounding the Ring of Brodgar.

The results showed that building to the south-east of the stone circle stopped abruptly and that an area around it was maintained as a definite “no-go” area – building-wise at least.

North-west of the Ring of Brodgar, the lack of activity continued until the Dyke o’ Sean – another Ness-spanning wall that runs from loch to loch. Beyond it activity resumed, with the surveys confirming a huge concentration of archaeological features, including structures, boundaries and enclosures..

Gradiometer survey results showing the concentration of archaeology (in black) at the south-eastern tip and north-west of the Ring of Brodgar. (ORCA/Landscapes Revealed 2020)

Three years later, in 2007, excavation confirmed that the building cut-off point was defined by the path of the Ness’ northern boundary wall – the southern limit of an apparently significant area in the Neolithic.

What did this enclosed landscape space represent? Why was it apparently inappropriate to occupy or raise structures within? We don’t know.

But the fact that it was avoided in prehistory and that its boundaries were clearly defined by a pair of monumental stone walls (and possibly a third) is surely more than coincidence.

We are left with a sense that we are looking at a place separated off from the “everyday” world. An area that was deliberately kept apart – symbolically and physically – from the rest of the landscape.

Dyke o' Sean Aerial
Aerial view, showing a section of the Dyke o’ Sean, flanked by pools of water. (

Applying his theory of domains of the living and dead from Stonehenge/Durrington Walls to the Stenness area in 1998, Professor Mike Parker Pearson pondered whether the area where the lochs of Harray and Stenness meet marked, like the River Avon, a boundary between the domains of the living and the dead.

In a paper presented at the Neolithic Conference in Kirkwall in 1998, Prof Parker Pearson suggested that the Standing Stones of Stenness, with its central hearth and surrounded by evidence of feasting, settlement and activity, represented life and the world of the living.

In stark contrast, the Ring of Brodgar, with its marked lack of domestic activity and surrounded by a complex of Bronze Age burial barrows, represented death or a spiritual domain of the ancestors.

As such, he suggested the procession between the two stone circles could be seen as a symbolic journey from life to death.

Whatever the situation, it does seem that the two walls enclosed a space set apart from “everyday” life and perhaps connected with the stone circle. Or was is simply perceived as being distinctly different and as such avoided?

How high?

Viewing the remains of the northern boundary wall there is no doubt it was a monumental construction.

Its width is clear for all to see but was this matched by its height?

The excavated wall sections survive to a height of 0.65 metres, but, obviously, we cannot tell from these how tall it once was. Its sheer width, however, implies it was a construction of considerable height. Why build a four-metre-wide wall if you were not intending to match the width with height?

In addition, compared to its Trench J neighbour, Structure Five, the wall’s basal course was found to be deeply pressed into the underlying glacial clay. This suggests it supported a wall of considerable weight – and probably height.

The southern boundary wall survived to a height of 1.8 metres, so it seems unlikely the “Great Wall” was any different. But is there any evidence?

The set of 'steps' - the second to date - found tied into the structure of the northern boundary wall in 2022. (Sigurd Towrie)
2018: The first set of ‘steps’ tied into the northern boundary wall. (📷 Sigurd Towrie)

Near the wall’s north-western curve, excavation in 2018 revealed a stone, step-like feature tied into the fabric of the inner face.

Trench J was extended again in 2022, fully exposing the area between Structure Five and the wall. This revealed a second set of steps.

Both sets of steps were set into the wall face, leading up in the same direction, and the wall face behind them curved slightly outwards to support now-missing higher steps.

If you are building something that requires steps to scale, or at least see over, it implies a fair height.

The presence of steps also suggests that access to the top of the wall was required – something that might go some way to explain the wall’s width. Was it more than just a boundary but perhaps a highly visible “stage” or platform?

If so, how was it used? Was is involved in the ceremonies or events relating to activity within the Ness complex? Or just another way to highlight the “differences” between those on either side of the wall? We can only speculate.

The two sets of possible steps in the northern boundary wall. (Scott Pike)
2022: The two sets of steps in the northern boundary wall. (📷 Scott Pike)

The outer face

Until 2023, only a small portion of the wall’s outer faced had been exposed, so another trench extension was opened across its width to reveal more.

This highlighted, again, the contrast between the two wall faces – the inner face, which used large boulders and rougher stones, and the outer wall face, which was made up of courses of flagstone slabs, carefully selected and laid.

These had been quarried locally, and not formally dressed, instead utilising the natural bedding planes and fracture lines running through the rock to create the building blocks we see today.

The extension showed, once again, that the wall was meant to look best from the outside…

A line of substantial stones was found embedded in the ground some distance from the base of the wall. These were collapsed masonry that had fallen from a higher section – apparently pushed from the top of the monumental wall during its dismantling.

Their distance from the outer wall face – and the fact they fell long enough to invert – suggests the wall stood at least 1.5 metres high and probably much more.

3d models

The southern boundary wall

August 2009: Trench R investigating the path of the ‘Lesser Wall of Brodgar’. (📷 ORCA)

In 2009, an exploratory trench was inserted over a large, linear geophysical anomaly to the south-east of Trench P.

Trench R confirmed the presence of a second isthmus-spanning wall, but one that was considerably different to its northern counterpart.

With a width of two metres (6ft 7in), the “Lesser Wall of Brodgar” was narrower but survived to a height of c1.8 metres (5.9ft).

It exhibited finer masonry and was built using flagstone slabs, rather than large stone blocks, and had been raised on top of the remains of earlier buildings. The wall’s outer face – the side facing the Stones of Stenness – was also paved along its base.

The position of the 'Lesser Wall' in relation to the two Lochview standing stones. (ORCA)
The position of the ‘Lesser Wall’ in relation to the two Lochview standing stones. (📷 ORCA)

Unlike the northern wall, the geophysics did not show anything that could be interpreted as an entrance. The wall does, however, seem to relate to the two standing stones at its northern end, perhaps suggesting they were part of an entrance feature.

The occurrence of stone pairs at entrances is something we have pondered here.

When were the two walls built?

The paving running along the base of the 'Lesser Wall' revealed in 2010. (ORCA)
2010: The paving running along the base of the ‘Lesser Wall’ revealed. (📷 ORCA)

The northern wall was built on virgin ground – constructed directly on top of natural boulder clay. Although this hints that it was probably early in the site’s history, we cannot say for sure.

But the fact it respects Structure Five, and curved around its northern end, suggests to two are roughly contemporary, dating to around 3300BC.

Sarah excavating at the bottom of the 'Lesser Wall of Brodgar' in Trench R in 2010. (ORCA)
2010: Sarah excavating at the bottom of the ‘Lesser Wall of Brodgar’ in Trench R. (📷 ORCA)

We think the southern boundary wall was raised around the same time, but here there is a major difference. The “Lesser Wall” was raised on top of the remains of earlier buildings.

What this suggests is that the complex – or its predecessor – was standing when a decision was taken to enclose it with monumental walls.

But the significance of the “Great Wall” did not last.

By around 3000BC – two centuries or so after the construction of the piered buildings in Trench P and a century before Structure Ten – the wall had been dismantled to its current height. [1]

The southern wall, however, remained standing until the end of the complex.

So why was the “Great Wall” demolished?

Probably because it no longer served as a site boundary and had been replaced.

An exploratory trench over the wall revealed what could be more buildings, and a possible hearth. This and geophysical scans suggest that structures spilled out to the north-west, beyond the original confines of the wall.

In addition, the remnants of another large ditch have been found to the north-west, discovered in section when the shore path along the Loch of Harray was built. Four metres wide and one metre deep, this huge earthwork – like those around the Ring of Brodgar, Stones of Stenness, Maeshowe and Ring of Bookan – seems to have enclosed the buildings we now suspect lay beyond the “Great Wall”.

What this tells us that the boundaries were not fixed but, like the Ness complex itself, changed over time:

“They made dramatic statements for a time before being abandoned, dismantled or reworked to serve other purposes.” [1]

An enclosed precinct?

2016: Aerial photo showing the path of an apparent cropmark (solid line) suspected to be the route of the enclosing wall. (📷 Scott Pike)

Geophysics suggested that the northern and southern boundary walls both ran across the width of the Ness and curved at the edges of the isthmus. As we have seen this was confirmed in Trench J, with the exposed section of the “Great Wall” curving beautifully at its northern end.

This led to the suggestion that the two boundary walls were connected by another pair running north-west to south-east and which completely enclosed the site.

But although geophysics showed apparent linear features running between both ends of the two confirmed boundary walls, excavation has drawn a blank.

Trench N, opened to investigate the extent of the ‘Great Wall of Brodgar’. (📷 ORCA)

The “Great Wall” definitely curves at its northern end and runs south-east for a short distance. Excavation in 2018, however, confirmed that it stopped abruptly and did not continue along the length of the Ness.

Investigating the boulder clay beneath huge stones forming the wall revealed, as expected, large depressions caused by the weight of the construction.

There were no depressions south-east of the wall end. At this cut-off point the boulder clay was unmarked – which it would not have been had a former section of the wall been dismantled or robbed.

At the opposite, western, side of the Ness what appeared to be cropmarks suggesting a long, linear feature following the path of a hypothetical connecting wall were noted from aerial photographs in 2017.

A new trench – Trench Y – was opened in 2018 but, again, there was no evidence of a connecting wall. From both sides of the Ness, the evidence there were no connecting walls – at least not on a par with the northern and southern walls – was stacking up.

While it may be that a less substantial boundary marked the south-western and north-eastern edges of the complex, there is another possibility.

We know that walls were not the only things that separated and defined space in Neolithic Orkney. The most obvious examples are the huge ditches that surrounded the Ring of Brodgar, Ring of Bookan, Maeshowe and the Stones of Stenness.

At other sites throughout Britain and Ireland, water features were also drawn on to enclose or define areas. [1]

The concept of water as a boundary in Neolithic Orkney has been suggested before. Professor Colin Richards has argued that the ditches around the Stones of Stenness, Maeshowe and the Ring of Brodgar were all water-filled — at least some of the time — further restricting access to the interior of the monuments, physically and symbolically. [2]

As well as containing and enclosing the monument, the Ring of Brodgar’s ditch and two opposing causeways controlled movement through the stone circle.

This north-west to south-east movement may have applied to the entire Ness – a procession that was interrupted and defined by a series of walls and bounded on both sides by the waters of the lochs.

When it came to the Ness, perhaps:

“… a limit of sorts was set by the isthmus itself, and by the water of the two lochs. Although water levels had been lower at the beginning of the period, by the late Neolithic, the loch margins were not that far removed from where they are today. In these conditions, the line between land and water may have served as an equivalent for walls.” [1]


  • [1] Card, N. and Edmonds, M. (2020) Setting boundaries. In Card, N., Edmonds, M. and Mitchell, A. (eds) The Ness of Brodgar: As it Stands. The Orcadian: Kirkwall.
  • [2] Richards, C. (1996) Henges and Water: Towards an elemental understanding of monumentality and landscape in Late Neolithic Britain. In Journal of Material Culture, 1(3), pp.313-336.