LIDAR survey 'unearths' 300 historic Scottish sites

Over 300 new archaeological sites have been found in Caithness – some dating back 3000 years – in a survey which is “beginning to rewrite the history of northern mainland Scotland”.

The work was carried out using a technique know as Light Detection and Ranging (LiDAR) which uses a laser to scan the ground from an aeroplane.

The survey was commissioned by Baillie Windfarm Ltd after it was required to record the landscape surrounding the nationally significant cluster of Neolithic chambered cairns at Hill of Shebster. The company asked AOC Archaeology Group to carry out the work.

The main focus of the survey was Cnoc Freiceadain, a prominent shoulder rising above the northern coast of Caithness, which is the site of a spectacular group of Neolithic monuments, including two long cairns and a series of stone settings.

AOC Archaeology managing director Dr Andy Heald, who has worked in the far north, was delighted with the results.

“As well as providing spectacular new images of the previously-known monuments around Cnoc Freiceadain, the survey revealed over 300 new sites,” he said.

“The most prominent archaeological features detected relate to settlement and agriculture dating to around 3000 years ago on one hand and to post-medieval farming on the other.

“In many areas, the survey has allowed the identification of palimpsests of agriculture and settlement, where medieval and later rig and furrow systems overlie much earlier cairnfields, interspersed with the fragmentary remains of 3000-year-old hut circles and associated enclosures.

“This ground-breaking survey offers an unparalleled opportunity for further study of the development of the modern Caithness landscape. It is also clear from the LiDAR survey that re-analysis of large areas of Highland Scotland is likely to produce numbers of new monuments and that fragments of the prehistoric farming landscape may remain beneath areas of later activity.

“The data set constitutes an invaluable research tool and an unparalleled means of preserving the landscape of 21st century Caithness by record.”

Dr Heald said the far north is well known for its spectacular archaeology but the LiDAR survey has provided a wider, hidden landscape.

“This survey is beginning to rewrite the history of northern mainland Scotland,” he stated.

Dr Heald explained that modern scanners can fire thousands of laser pulses a second and by mounting the instrument on an aircraft very large areas can be covered in high resolution in short spaces of time.

“Nearly a billion points were collected during the recent LiDAR survey. Once the raw data was gathered, it was processed to create very high-resolution elevation models, detailed enough to record field boundaries, walls and ancient monuments, giving an unparalleled view of the archaeology in the area,” he said.

“One of the main aims of the project was to present the results of the Baillie survey online, in a format that allows users to explore the data, identify features of interest and explore monuments that are familiar to them.”

A dedicated website, which showcases the survey results, has been produced, linked to Highland Council’s Historic Environment Record and gives visitors a “virtual tour” of Caithness archaeology.

“The website provides a unique window on Caithness’s past and will be a valuable resource for archaeological research and interested visitors alike,” added Dr Heald.