A new discovery of archaeological remains, thought to be those of a "curtain wall" extending up to 80 metres and dating from the 17th century, has been made at Carrickmines Castle in south Co Dublin.
The area of the remains, on a hillside to the south-west of an existing farmhouse, indicates the castle itself was a considerably larger complex than was originally thought, according to archaeologists.
The new finds, which come as the archaeological dig at the castle enters its fifth year, is not in the line of the motorway or the controversial Carrickmines interchange.
The curtain wall is separate to the "fosse" - essentially an outer defence - and archaeologists are hoping the find will reveal more information on how the castle was defended.
Carrickmines campaigner Mr Ruadhán MacEoin said the discovery of the curtain wall would suggest the original keep and its walls were on a scale similar to that of Trim Castle in Co Meath. "This means it is much bigger than we originally thought," he said.
Archaeologist Dr Mark Clinton, who led the original dig at the castle, said it represented "a very significant find".
Dr Clinton said it had been his ambition to excavate the site in the early days of the dig but he was discouraged from doing so. He said the pattern of the excavation was now "turning into a soap opera" and added: "It is good that it has been found, but you have to wonder at the official silence about the discovery."
Dr Clinton said he had learned that tree-felling at the site yesterday had damaged archaeological remains of wells which served the castle and remains which were possibly those of a chapel. "These are what Séamus Brennan [the former minister for transport] wanted to keep and they have felled trees on them." Dún Laoghaire-Rathdown County Council said, however, that no artefacts were damaged during the tree-felling, which it insisted was carried out under archaeological supervision.
The council's director of transportation, Mr Eamon O'Hare, said it had always been known or suspected that there were additional artifacts at Carrickmines and this had been the council's difficulty in considering moving the interchange and motorway.
"Wherever we moved it, there was always the likelihood that we would find new material," he said. He also revealed that the northern carriageway of the motorway had now been "black-topped", which is the final covering, while the southern carriageway is expected to be similarly finished within weeks.
A public inquiry into plans to widen the M50 starts on December 14th.
