An ancient fortress believed to be thousands of years old has been discovered in the ground under a popular play park.
Archaeologist Michael Gibbons discovered the bronze age building whilst carrying out field work in the Burren lowlands of County Galway in Ireland.
Measuring around 440 acres, the fortress is bounded on all sides by turloughs - a type of seasonal lake found only in Ireland near the River Shannon.
When filled with water the turloughs would have made it almost impenetrable to enemy forces looking to storm the structure.
Incredibly, it is believed to have been built around 3,200 years ago in what is now Coole Park.
The site at Coole Park has been known but its origins and age were not understood until the recent studies, GalwayBeo reported.
Gibbons had been using sophisticated LiDAR equipment when he made the discovery the fortress was likely to have been built between 800 and 1200 BCE, between 2,800 and 3,200 years ago.
He said: “We know there were numerous roundhouses within it, that they’re metalworking, and that they’re making high status artefacts.”
He had been working on an educational project known as Muintearas, which is attempting to protect and preserve Ireland’s traditional culture and language when he made the discovery.
Seán Ó Coistealbha, Muintearas CEO, said: “Enormous work would have gone into constructing it by men and women in ancient times
"We are just skirting around the stone ramparts of this community with a wealth of information yet to be discovered."
The size of the building suggests it could have housed hundreds of people.
It comes as images showed an abandoned slate quarrying village in north Wales which was unused for a century.
In the northwest of Wales there are some of the largest and most productive slate quarries in the world stretching from the Nant Ffrancon valley in the east to Nantlle.
The region became known to have "roofed the 19th century world", with a significant effect on the lives of the region's people and communities as well as the landscape with its traces still found today.
And for urban explorers there are abandoned sites including the old Talysarn village that was once used by slate miners before the population was relocated further west where there still remains around 2,000 people living there today.
