A MYSTERIOUS ring fort in Co Tipperary holds “massive potential for discoveries” according to archaeologists who have carried out the first survey of the site.

Their initial findings suggest that the site may have been used for Bronze Age sporting contests in an arena that is the ancient equivalent of Semple Stadium.

Archaeologists have long been curious about the origins of the Rathnadrinna Fort located about 3km south of the Rock of Cashel – one of Ireland’s most important heritage locations and seat of the High Kings of Munster.

The unusually large and distinctive landmark is still subject to many of the traditional taboos surrounding fairy forts. Archaeologists say that many people in rural areas still believe it is unwise to enter a fairy fort or to cut down perimeter trees or vegetation.

Ian Doyle, head of conservation services and archaeology with the Heritage Council, said it was traditionally believed that the fort was a “defended farmstead” of a type commonly built in Ireland about 1,200 years ago.

But while the “average run-of-the-mill fairy fort” is ringed by one defensive perimeter ditch, “Rathnadrinna Fort is quite rare because it has three rings”. Despite the historical significance of the landscape, the fort has never been excavated.

Mr Doyle said “when you think of Tara, the countryside surrounding the Rock of Cashel must hold massive potential for discoveries”. This led the council to fund a survey of the site which was carried out by a team of archaeologists led by Cashel-based Richard O’Brien and the Co Mayo company Earthsound Archaeological Geophysics.

Using highly sensitive equipment, the soil was subjected to “high-resolution magnetic imaging” – similar to an MRI scan. It is the first time that any of the fairy forts in the countryside surrounding the Rock of Cashel has been surveyed in this manner.

Speaking to The Irish Times about the results, Mr O’Brien said that “none of the traditional evidence associated with ring forts – such as houses, hearths or rubbish pits – was found”. Instead, the team discovered that the site may have been first used 3,000 years ago during the late Bronze Age.

He said one of the most exciting discoveries was evidence of a Stonehenge-style circle of wooden posts suggestive of “a ceremonial or ritual role for the fort”.

Mr O’Brien said the use of the site would have changed down through the centuries and the survey results indicate that it had “a royal function”. But the most intriguing possibility, he said, was that the “vast interior area which is much larger than most ring forts is like a sports arena”.

Rathnadrinna translates as the “Fort of the Contest”, he added.