A Scottish crannog older than Stonehenge has been mapped in new detail using a shallow-water 3D imaging technique.
Archaeologists at the University of Southampton have excavated and documented a large wooden platform concealed beneath what now looks like a stone island in a Scottish loch.
Using stereophotogrammetry, they recorded the artificial island above and below the waterline as one continuous structure. This gave them a view of the site that neither land survey nor underwater survey could have produced on its own.
A hidden island gains detail
Working with the University of Reading, the researchers studied the ‘crannog’ in Loch Bhorgastail on the Isle of Lewis and revealed a structure built more than 5,000 years ago. Their fieldwork exposed layers of timber and brushwood beneath the island’s stone covering, as well as hundreds of submerged pieces of Neolithic pottery in the water around it.
University of Southampton archaeologist Dr. Stephanie Blankshein explains: “Crannogs are small artificial islands that are typically thousands of years old. Hundreds exist in the lochs of Scotland and many remain unexplored or undiscovered.
“While crannogs were long thought to have been built, used and re-used, mainly between the Iron Age and the post-medieval period, we now know that some were first constructed much earlier during the Neolithic between 3800 and 3300 BC.”
Older than Stonehenge
Across several years of fieldwork, the archaeologists used excavation, coring, advanced surveying, and radiocarbon dating to reconstruct the development of the Loch Bhorgastail crannog.
The site was first created more than 5,000 years ago, making it older than famous monuments such as Stonehenge. It began as a circular wooden platform about 23 meters wide, covered with brushwood. Roughly 2,000 years later, during the Middle Bronze Age, people added another layer of brushwood and stone. About 1,000 years after that, the site saw another phase of activity during the Iron Age. An underwater stone causeway connects the island to the loch shore.
