Islands of Stone: Neolithic Crannogs in the Outer Hebrides

GUEST BLOG: ‘Islands of stone’: Neolithic crannogs – possible ‘ritual’ sites in Lewis that are older than Calanais

Map of Neolithic sites: Fraser Sturt & Duncan Garrow

The stone circle complex at Calanais is considered by many to have been part of a highly significant ritual landscape, where groups of people would have gathered in order to celebrate special events and to conduct ceremonies. Recent work in Lewis undertaken by the Universities of Reading and Southampton has uncovered further evidence of Neolithic ‘crannogs’ close by. These artificial islets, constructed in freshwater lochs, are around 500 years older than the stone circles at Calanais. These sites too appear to have been special places where groups of people gathered to conduct low-key ceremonies and perhaps small-scale feasting events. It is therefore possible that a full understanding of these intriguing sites will shed further light on ritual activity in the wider Carloway area (and beyond) and thus on the origins of Calanais. In this article, two directors of the ‘Islands of Stone’ Neolithic crannogs project summarise their work so far and provide information about a new project, starting in 2020, designed to investigate these intriguing sites.

During the summers of 2016 and 2017, Duncan Garrow (University of Reading) and Fraser Sturt (University of Southampton), working with a team of experts, carried out underwater and boat-based archaeological survey and excavation work on three of the six known Neolithic islet sites in Lewis – Loch Langabhat and Loch Bhorghastail, near Carloway and Loch Arnish, near Stornoway.

Loch Langabhat: Fraser Sturt

These ‘crannogs’ – artificial islands constructed in lochs – are a numerous, geographically widespread and intriguing category of archaeological site. Unusually, this one site type was constructed in many different periods of Scotland’s prehistoric and historic past. Most scholars generally considered them to have been built, used and re-used from the Late Bronze Age (c. 1000 BC) to the medieval period (c. AD 1500). Hugely significantly, our work in Lewis confirmed that the origins of some of these sites in fact lie 3000 years earlier than previously thought, in the Neolithic (c. 3500 BC), the period when farming, pottery and burial monuments first arrived. Over 400 crannog sites are recorded in Scotland, and many more no doubt lie undetected. The Outer Hebrides represent a particular hotspot in their distribution, with 150 potential sites identified across the island chain. Mostly unexcavated, it now seems conceivable that some of these are also in fact Neolithic.

Unstan Bowl at Loch Arnish: Chris Murray

The Neolithic crannogs project was only conceived in the first place due to the curiosity of local diver and keen archaeologist Chris Murray. Chris was intrigued enough by one islet, spotted whilst out walking his dog, that he took the decision to dive around it. What he found there – a series of Neolithic pots lying on the loch bed, all remarkably well-preserved and several in a remarkable state of completeness – was totally unexpected, both by Murray and by the archaeological community at large. Following on from this discovery, Murray and Mark Elliott (then conservation officer at Museum nan Eilean, Stornoway) embarked on a sustained search of other accessible islet sites across Lewis. Notably, in several cases, they found similarly impressive assemblages of well-preserved Neolithic pottery.

Building on their findings and working in close collaboration from the start, our recent work has included: underwater geophysics and diver survey, underwater and aerial photogrammetry, real-time kinematic GPS survey, palaeo-environmental coring and traditional dry-land excavation, along with radiocarbon dating. The newly discovered Lewis islet sites are extremely impressive – massive piles of rock (c. 20m across and up to 6m high) constructed within what would have been lochs in the Neolithic. Their monumental scale is comparable with local stone-built passage tombs of the same date. Diver surveys have identified worked timbers indicating that the mound structures were revetted; stone causeways out to two of them were also observed. Substantial quantities of pottery and quartz have been found on the loch beds around them. The preservation of ceramics – some vessels complete, many largely intact – is perhaps unique within the British Neolithic.

Our work has now conclusively demonstrated that human-made, artificial islets were a key feature of the Neolithic in this region. Radiocarbon dating indicates that they were in use from approximately 3650-3350 BC, several centuries before Calanais was built. Intriguingly, on the basis of excavations carried out at Loch Langabhat in 2017, it appears that these islet sites do not seem to have been settlements – their surface area is very small and they have no obvious buildings. They appear to have been special purpose locations which saw significant deposition of material culture into the water, perhaps in association with feasting and other ceremonial events. This image shows the current water level shown in blue and pottery finds in red. You can read more about this previous work here.

We were very pleased to hear recently that our application for further funding (from the Arts and Humanities Research Council) had been successful. This will enable us to continue our work investigating Neolithic crannog sites, in conjunction with project researcher Stephanie Blanskhein (Southampton) and Angela Gannon and colleagues at Historic Environment Scotland. We were supposed to be carrying out further excavation and survey work at Loch Bhorgastail in July 2020, but sadly have now had to postpone until 2021. For more information about the ‘Islands of Stone’ project and to keep up to date with what we get up to over the next few years, please visit our website.