The recent prolonged dry spell of weather has revealed some ‘brand new’ archaeological sites – formations which would normally be concealed under the lush soil and vegetation of agricultural land. New Iron Age structures in the Borders, and a temporary Roman camp near Peebles in Southern Scotland have both been discovered, sites not a stone’s throw off Merlindale on The Merlin Trail!
The Scotsman’s Heatwave crop marks reveal lost ancient sites in Scotland article reports that,
“Iron Age souterrains (underground stone structures) in the Borders – a rare find in this part of the country – and a Roman temporary camp at Lyne near Peebles have been identified by Historic Environment Scotland’s aerial survey team.”
These sites have been made visible as the sun has scorched the grass, revealing the shape of rock below.
The recent dry weather has given archaeologists the best chance to discover new sites, using aerial cameras, since 1976! It is a practice that Aerial Survey Project Manager at Historic Environment Scotland, Dave Cowley explained has been carried out since the 1930s – they have built up quite a picture of the Scottish landscape using this technique and both the skills and knowledge they have developed in recognising and interpreting these sites.
He said: “We depend on dry years to bring out the buried remains in the crops [which] adds to our ability to see into the past.”
He goes on to explain, in a BBC South Scotland article that,
“the process is one that would be familiar to any gardener, who might see the contrast in their lawn between a path that has been recently turfed over, and an old flower bed that is now covered by the lawn. The area of grass over the old path, for example, will start to burn out sooner, while the former flower beds will stay greener. That’s basically because the plant has different amounts of water and nutrients and so on.”
This concept can be clearly seen in this image from The Times ‘Ancient sites uncovered as dry weather makes mark‘ article:
Dave Cowley continues,
“In either grass or arable crops, what we see from the air is the response of the crop to changes in the underlying soil depth and the moisture at that depth.” “From the point of view of the crops, a ditch is a ditch, whether it was dug five years ago, by a Roman legionary, or five thousand years ago around a large ritual monument.”
The soil is a lot deeper in these ditches and so it retains more water and nutrients during dry spells.
These illustrations from the RCAHMW show a timeline of how the process occurs over the years:
The Royal Commission on the Ancient and Historical Monuments of Wales image showing timeline from Iron Age to present day souterrains
And this example, from Historic Environment Scotland, exemplifies how the parched grass shows up a curved shape which is probably an Iron Age passage or souterrain:
Image from Historic Environment Scotland, captioned: A newly discovered Roman Temporary Camp at Lyne [near Peebles] revealed by lines in the landscape
Big Think‘s ‘Strange Maps’ feature shares some more pictures of scorched fields that have revealed some never-before-seen images of Britain’s past. Below, an image of how the drought has revealed the medieval castle mound at Castell Llwyn Gwinau, in Wales:
It makes us wonder what could be lurking around, waiting to be discovered nearby some of our Merlin Trail locations. Anyone out and about with a drone before the weather breaks? Please do let Historic Environment Scotland know, share your experiences and send us your photos!
Historian Tom Holland described this current, curious phenomenon as,
“The bones of our past sticking through the flesh of the present”.
Experts like Historic Environment Scotland’s Dave Cowley are rushing to document these discoveries before the more typical summer holiday rain descends and these fascinating bones of our past disappear once again…
Main [top] image, from Historic Environment Scotland: Three small round ditches and one square ditch reveal the sites of probable Iron Age burials