It’s summer 2018, and Britain is in the grip of a searing heatwave. After months of weather that is strikingly hot, the ground is barren and parched. But in the skies above, archaeologists are making some startling revelations about the landscape. These are secrets that have lain hidden for thousands of years.
Throughout June, July and much of August 2018, Britain basked in record-breaking temperatures, with highs topping 35 °C. In fact, it was the hottest summer ever recorded in England. The average of 17.2 °C beat the previous record set during the famous heatwave of 1976.
As people across the country enjoyed the long run of warm weather, the tourist industry boomed. But while seaside resorts and outdoor attractions reaped the benefits, the heatwave brought downsides too. For example, the extreme temperatures sparked wildfires in places like Greater Manchester. Hosepipe bans came into force across Northern Ireland too.
Meanwhile, the famously green countryside of the United Kingdom began to suffer. As drought kicked in, crops began to fail, leaving the vegetation wilted and sparse. But even though it was a concerning time for the region’s farmers, the desolation of Britain’s fields and hillsides had a surprising upside as well.
For archaeologists, the heatwave gave the ideal conditions to study what are known as crop marks. These are visual imprints on the landscape that allow experts to determine where certain features might once have been located. Over time, these marks have proved an important tool in mapping the forgotten landmarks of the British Isles.
Apparently, different archaeological features can cause crop marks to form. For example, if a wall is buried underground, the vegetation growing above it will suffer as it has limited access to water and fertile soil. Meanwhile, filled ditches can provide a higher level of nutrients, resulting in healthier, greener growth.
Ever since the 18th century, experts have used these crop marks to learn more about the structures and buildings that once existed in the landscape. This is true even for those that have been buried for thousands of years. And when conditions are exceptionally dry – such as during a heatwave – these reminders become even more pronounced.
“This spell of very hot weather has provided the perfect conditions for our aerial archaeologists to ‘see beneath the soil’ as crop marks are much better defined when the soil has less moisture,” explained Duncan Wilson from Historic England, a governmental agency that works to protect ancient landmarks.
Towards the end of June, Dr. Toby Driver, an aerial investigator with the Royal Commission on the Ancient and Historical Monuments of Wales, took to the skies to get the best vantage point of crop marks across the country. Traveling in a light aircraft, his aim was to record details of the imprints. And he had to get that done before the heatwave ended and conditions changed.
Amazingly, some of Driver’s discoveries had been lost for thousands of years. For example, near the village of Magor in southeast Wales, lines of greener vegetation marked the spot where a small Roman fort once stood. Meanwhile, just four miles away in Langstone, Newport, the heatwave had revealed location of an ancient farm.
Elsewhere, the heatwave had revealed more information about existing sites, such as the Roman villa or farm located in the Monmouthshire village of Caerwent and parts of Cross Oak Hillfort, an ancient settlement in Powys. Furthermore, crop marks also painted a strikingly clear picture of Castell Llwyn Gwinau. This is a medieval mound in Ceredigion that has almost disappeared through years of plowing.
Meanwhile, in July and August, archaeologists from Historic England also took to flying across the landscape and snapping photographs of crop marks on the ground below. And according to experts, the results have been the best since 2011. In that year, more than 1,500 new sites were revealed.
Among the prehistoric features revealed were two rectangular crop marks located close to the Buckinghamshire village of Clifton Reynes. Apparently, they represent the remains of a cursus monument – a type of Neolithic structure typically dating from the fourth millennium B.C. And even though the left-hand structure had previously been studied, the one on the right had lain hidden until 2018.
According to experts, there are more than 100 known cursus monuments across England today – many discovered by aerial archaeologists. Interestingly, it’s believed that they once served as processional walkways and possibly as a way of dividing the landscape. And amazingly, some of them stretch as many as six miles long.
In Pocklington, a market town in the Yorkshire Wolds, aerial archaeologists spotted four crop marks that show where the ditches surrounding ancient burial sites once stood. Thought to date back to the Iron Age, similar mounds have been found to contain grand burials complete with grave treasures – making this discovery a particularly exciting one.
Up and down the country, aerial archaeologists continued to uncover astounding evidence of Britain’s ancient past. In fact, in Cornwall alone, dozens of new sites were discovered. These included the remains of an Iron Age settlement in the village of St. Ive. Also found were more prehistoric structures on the coast at Lansallos.
Other notable discoveries included a possible ancient cemetery in the Suffolk village of Stoke by Clare and the remains of a Roman farm located in Bicton in Devon. And interestingly, some more modern relics were uncovered as well. These included the lost 16th century structures that once surrounded Staffordshire’s Tixall Hall.
“The discovery of ancient farms, settlements and Neolithic cursus monuments is exciting,” enthused Wilson. “The exceptional weather has opened up whole areas at once rather than just one or two fields, and it has been fascinating to see so many traces of our past graphically revealed.”
Meanwhile, Historic Environment Scotland has announced similar findings in the north of the U.K. These include a temporary camp erected by Romans and Iron Age remains close to the border with England. Here, archaeologists claim that the conditions of summer 2018 were the best in more than 40 years for spotting crop marks.
But although the amount of new discoveries made during the 2018 heatwave is impressive, many of these sites will never be excavated by professionals. However, some of them can now be given protection, preventing damage from factors like development and deep plowing – hopefully preserving them for future generations.