The heatwave of last summer revealed a hidden treasure trove of ancient monuments across Ireland, satellite pictures reveal.
By examining images on websites such as Google Earth, experts have managed to pinpoint a series of ringforts and henges dating back centuries.
Many of them can be seen in crop fields where the farmers were unlikely to have known they existed before the drought of 2018 started to reveal hidden shapes in the fields.
Anthony Murphy of Mythical Ireland, with Ken Williams, found the first and most well known discovery of the heatwave - a previously unknown henge near Newgrange which continues to make international news.
More recently, Mr Murphy has been examining new Google images, and said as a result he has discovered a huge number of previously unknown monuments, most of them in crop fields in the tillage-rich areas of seven different counties.
Meath, Dublin, Kildare, Carlow, Wicklow, Laois and Kilkenny are all covered by the June 2018 satellite images which have recently been added to Google Maps/Google Earth.
He said that in many cases there are no marks or traces left on the surface so the farmers and landowners will be unlikely to know they even exist.
He believes that some are small ring-ditches, maybe 20 metres or 30 metres wide.
There are also some "truly enormous" structures like ringforts and enclosures, in some cases measuring 100 metres wide and more.
"The largest structure visible in the Google imagery is in Co Dublin and measures a staggering 350 metres wide," Mr Murphy said.
In October the Department of Culture, Heritage and the Gaeltacht said the heritage sites discovered during the summer heatwave near Newgrange have the potential to transform our understanding of that landscape.
At the time, it released a list of 71 new national monuments in 12 counties reported to it from June to August this year.
It said the majority were in counties Louth and Meath, with 13 and 25 new monuments respectively.
But discoveries were also made across the country and include possible rock art and prehistoric art as well as enclosures, bronze-age cemeteries, ring ditches, souterrains, ecclesiastical enclosures and a road.
Now Mr Murphy is hoping to pinpoint even more ancient structures to add to that list.