Islands of Stone

Fieldwork 2021

2021 Field Season

Following on from previous survey work (carried out in 2016 and 2017), a more substantial excavation was undertaken on and around the Neolithic crannog in Loch Bhorgastail in 2021. This involved both terrestrial and underwater excavation.

Diving underwater

On the surface of the islet, vegetation and peaty soils were removed across approximately 60% of its extent (above water), revealing the full structure and character of stones across the site: a flat stone base, an outer ‘ring’ and a cairn-like feature on the eastern side. Following this work, a small 2 x 1m sondage was excavated through the stone ‘base’ of the islet. This, rather unexpectedly, revealed a sequence of brushwood/heather and silty layers, suggesting that the stone phase of the crannog was pre-dated by a timber construction of some sort! Burnt deposits including peat ash were also identified along with numerous sherds of Neolithic pottery. Given the small size of the sondage and its depth below loch levels (causing it to quickly become waterlogged), it was not possible this field season to further explore this early phase of the site.

Extent of terrestrial and underwater excavation viewed from the east.

Adjacent to the stone islet, an underwater trench was excavated extending out from the SE quadrant; the main trench was 2 x 4m (plus a 1 x 2m extension immediately next to the stone islet). This trench revealed an extensive spread of laid timbers, overlain by brushwood layers and silts. To a considerable extent, this stratigraphy matched those observed in the sondage on-land. The pre-stone, timber phase architecture extended a considerable distance beyond the outer edge of the stone islet, with some timbers observed up to 7.5m from the outer edge of the stone islet!

Submerged timbers revealed during underwater excavation (1m scale bar).

Read the full interim report here.