In 2018 a drought struck parts of Ireland.
As the terrain changed, experts began noticing strange markings in the ground.
Where no one previously thought anything existed, ancient structures were revealed by nature.
As experts took aerial images of different parts of Ireland, they noticed ‘crop circles’ on the ground.
But these odd circles weren’t the product of little green man coming from outer space.
They were created by ancient cultures inhabiting the region more than 6,000 years ago.
Some of the sites are extremely old, others date back between a few hundred to a thousand years.
The draught revealed more than 50 previously unknown ancient monuments and an agricultural history going back thousands of years.
Anthony Murphy author and photographer with Mythical Ireland, has been recording ancient monuments in Ireland for more than twenty years.
Using Google Maps, countless monuments were eventually revealed.
He uncovered more than 50 sites previously unknown to researchers.
The sites are extremely hard to spot since no traces of them have been left on the ground.
It is also likely that people lived on top of some of these sites for hundreds of years without knowing they ever existed.
Timing was of great essence.
Google Maps is frequently updated with new satellite images. Massive forts, as well as different medieval enclosures, only became visible in the ground after the draught, and after Google Maps was updated.
Had the team looked at Google Maps just a few months prior to the draught, they would never have spotted the ancient sites. When the grass was healthy, the sites were well hidden.
The ancient monuments became visible, mostly in tillage fields, during drought conditions, when crops had been starved of moisture.
As explained by Murphy, “The ditch features retain whatever trace moisture is in the ground a little more effectively than the surrounding soil, and so the crops growing out of the archaeological features tend to be a tiny bit greener and healthier. From the air, what you get is a contrast between the healthier and less healthy crops, revealing the shape and size of the structures beneath the surface. It’s fascinating.”
The terrain starved of moisture revealed the ancient sites due to the weight of the ancient structures, as stones sank into the earth creating ditches.
These ditches are the reason why the sites were eventually revealed.
The ditches retain more water than the surrounding soil. Inside them, grass can remain healthier and hydrated more than the grass in the surrounding terrain.
This causes color variations to appear on the surface. Some terrain is brighter, some is darker.
As experts looked at updated Google Maps, they noticed these surface features.
After spotting the sites, they only had to go and confirm they were of archaeological importance.
“Some are small ring-ditches, maybe 20 meters or 30 meters in diameter, but there are some truly enormous structures like ringforts and enclosures, in some cases measuring 100 meters in diameter and more. The largest structure visible in the Google imagery is in County Dublin and measures a staggering 350-meter-wide,” explained Murphy.
“It’s an insight into agriculture and life in general in previous times. People have been farming the land in Ireland for around 6,000 years. The evidence of their settlements, and indeed their farms and of course their burial grounds, is literally everywhere.”
Anthony Murphy was “gobsmacked” on Tuesday night of this week when he discovered a never-seen-before giant henge monument in the Boyne Valley not far from Newgrange.https://t.co/3OFtBbz7jj
— Farmers Journal (@farmersjournal) July 11, 2018
As explained by Murphy, the last time such discoveries were possible was in 1976, the last time Ireland was struck by such severe droughts.