Tuesday, October 8, 2019

Neolithic crannogs - New Scottish Discoveries



Lough Gara
Introduction
In earlier posts I discussed the crannogs of Lough Gara on the border between Co Sligo and Co Roscommon in Ireland. Crannogs are partially or entirely artificial island, usually built in lakes, rivers, and estuarine waters of Ireland, Scotland and Wales. They are commonly made of timber and stone and are occasionally built on existing rocky structures. They are widespread in Ireland, with an estimated 1,200 examples while Scotland has 347 sites officially listed. 
It had been thought that these artificial islands dated from the Iron Age. We now know that crannogs were used for over five thousand years from the European Neolithic Period to as late as the 17th/early 18th century. Four Western Isles sites in Scotland have recently been radiocarbon dated to about 3640-3360 BC in the Neolithic period - before the erection of Stonehenge's stone circle.
Aerial View of crannog in Loch Langabhat, Scotland
BBC News Scotland, Highlands and Islands
Crannogs, or at least platforms, may have been built on Lough Gara in the Late Mesolithic (5500 to 4000 BC). However, the practice of building on the shallow shores increased during the Late Bronze Age (1200–800 BC) and again in the Early Medieval period around 600 AD. Some crannogs were used as late as the 17th century. The recent research in Scotland points to some crannogs there being much older than previously thought prompting a reappraisal of dates for these structures.
Fredengren’s survey of Lough Gara found piling, timbers and brushwood stretching over a 40m area of white marl along the north-east shore of Inch Island. The wood deposit formed three groups, 3-4 m apart. A small number of posts could be seen in the water. One of the vertical timbers produced a radiocarbon date of 4230–3970 BC, indicating activity in the latest phases of the Mesolithic, while a brushwood piece indicated a date in the early Mesolithic, showing that there was human activity on Inch Island around 7330-7050 BC (Fredengren, 2002).
A diver holds a Neoilithic (c 3,500 BC) Ustan vessel
found near a crannog in Loch Arnish, Scotland.
BBC News Scotland, Highlands and Islands
Isle of Lewis
 Archaeologists Dr Duncan Garrow, of University of Reading, and Dr Fraser Sturt, from the University of Southampton, investigated four crannog artificial islands in the Isle of Lewis in the Western Isles. At one of the sites well-preserved Neolithic pottery had previously been found on the loch bed. The archaeologists said the crannogs represented "a monumental effort" through the piling up of boulders on the loch bed, and in the case of a site in Loch Bhorgastail, the building of a stone causeway. The archaeologists believe it is possible other Scottish crannogs, and similar sites in Ireland, were also Neolithic.
Eight radiocarbon dates were recorded from the structural timbers used in the building of the four crannogs on the Isle of Lewis and six of these fell within the Neolithic era.  The research also shows for the first time that the pots were likely to have been intentionally placed in the water around the crannogs.
The condition of the nearly intact Neolithic ceramic vessels found in the water around the crannogs was described as “amazing” by Duncan Garrow, who co-authored the paper. “I’ve never seen anything like it in British archaeology,” he says. “People seem to have been chucking this stuff in the water.”

Neolithic crannog of Eilean Domhnuill,
North Uist, Scotland
Loch Tay
Since 1980 archaeologists have explored the waters of Loch Tay for crannogs and have excavated one at Oakbank, just off the village of Fearnan. Preserved in the loch's cold, peaty waters were structural timbers, food, utensils and 2600-year-old clothing. They even discovered a butter dish with butter still clinging to the inside of it.
In 1994 experimental archaeologists from the Scottish Trust for Underwater Archaeology reconstructed a crannog on Loch Tay using the same material as the original at Oakbank. The reconstruction at Kenmore involved building a thatched roundhouse on a timber platform 15m across, which was connected to the shore by a timber causeway 20m long. The whole structure is supported on 168 timber piles.
Considerable skill is required to build a crannog. The first stage was to create an artificial island out of timber piles. Alder trees, 8-10m long, were used for the piles. Considerable work would have been required to pull the alder piles into a vertical position. The original crannog builders then faced the task of how to drive the alder piles up to 2m into the loch bed using only Iron Age technology. Archaeologists think that a crosspole would have been lashed to the upright pile and twisted back and forth to create enough force to drive it two metres into the loch bed.
Rathtinaun crannog (Late Bronze Age),
Lough Gara, Co Sligo, Ireland.
Conclusion
Whilst it had been thought that crannogs dated from the Iron Age, we now know that they were used for over five thousand years from the Neolithic Period to as late as the 17th/early 18th century. Dating crannogs is complicated by multi-periods of occupancy as noted, for example, in the case of Rathtinaun crannog, Lough Gara, where the foundations date from the Late Bronze Age with evidence of reuse in the Early Medieval Period.
Archaeologists can only speculate as to why the Scottish crannogs were built, how they were used, and why they became places for pottery disposal. Vicki Cummings, an expert in Neolithic monuments from the University of Central Lancashire suggests the sites’ isolation, and the pottery that surrounds them, could point to rituals that marked life transitions like the passage from childhood to adulthood.
Paper co-author Duncan Garrow admits the research is only just beginning. His team plans to conduct a broader survey to date more crannogs in the Outer Hebrides. In the meantime, the Scottish findings provides support for the earlier Mesolithic and Neolithic dates recorded by Fredengren for some of Lough Gara’s sites.

Christina Fredengren (2002) Crannogs: A study of people's interaction with lakes, with particular reference to Lough Gara in the north-west of Ireland