Gardaí in Dingle, Co Kerry, are investigating the destruction of a major part of a 3,000-year-old promontory fort on the Dingle Peninsula.
The Dún Mór coastal promontory fort is "hugely important and, so far as is known, the biggest coastal promontory fort in the country", according to an archaeologist, Mr Michael Gibbons. It overlooks the Blasket Islands and the Skelligs.
Earthmoving machinery was used at the fort to flatten the earthen ramparts. An entrance and a standing stone with an ogham inscription were removed.
Gardaí who visited the site yesterday said the land had recently changed hands and the new owner may not have been aware of the significance of the site or if there were any restrictions on work on the land.
The owner was away until today, and could not be contacted for comment.
The work carried out on the site came to light when Mr Con Moriarty, a place names specialist, amateur archaeologist, mountaineer and walking tour guide arrived shortly before lunch yesterday to show the fort to a group of American tourists.
Upset by what he found, Mr Moriarty said the linear earthworks and some of the remains of the fortifications, including 700 metres of earthen ramparts, had been "flattened". "This is outrageous. This is one of the country's prime beauty spots."
Mr Gibbons, an archaeologist, who carries out much of the archaeological work on the monuments of the Dingle Peninsula, said the ogham inscription alone on a standing stone in the promontory fort pointed to the importance of the monument.
Listed as a national monument on the Sites and Monuments Record of Co Kerry, a survey carried out by the OPW over 20 years ago, it should enjoy protection, he said. However, the legal status of such monuments on private lands was sometimes "a grey area".
He described the destruction of Dún Mór as "an act of cultural sabotage".
Mr Gibbons said that this was just the latest incident in the destruction of listed and unlisted monuments on the peninsula and in Munster recently. He blamed "aggressive farming activity," in the form of land reclamation for the majority of the destruction.
The Dún Mór fort was a key navigational point along the west coast, probably because of its location at the headland of the peninsula, Mr Gibbons explained.
It was in use for a long period, from about 1,000 BC to around AD 600, he said.
Dún Aengus would fit "four to five times inside it", he added. "It dwarfs every other monument in the whole area." Within the fort there was a network of little fields.