A VIKING fortress of international importance has been uncovered at Annagassan, Co Louth. It is believed to be the longphort (ship fortress) of Linn Duchaill, founded in AD 841 – the same year as Viking Dublin.

“Finds of Viking ship rivets, cut-up Viking silver and looted Irish metalwork also appears to be amongst the excavated material,” said archaeologist Dr Mark Clinton.

A defensive rampart, consisting of a deep ditch and a bank, was excavated and, while the results of radio carbon tests are awaited to confirm the date, it “has all the appearances of the main fortification of the Viking fortress,” he said. The excavations have also uncovered part of a human skull, a whorl for spinning thread and a brooch pin.

Dr Pat Wallace, director of the National Museum, said: “This could be on a par with Woodstown in Waterford, which has been shown to be a pure Scandinavian settlement of the mid-ninth century during the raiding phase of the Vikings.”

Eamonn Kelly, keeper of antiquities with the National Museum, said attempts to identify this site date back more than 200 years, “and the significance of it is immense. It will be up there with all the major Viking sites in Europe.”

The current excavations, by professional archaeologists, began three weeks ago.

The discovery of the fortress, which is located on a stretch of land between the coast and the river Glyde, is especially exciting as it is on agricultural land and as such is “completely preserved”, he said.

Dr Clinton described the defensive ditch at Annagassan as “massive” and said it was clear the Vikings had built it across an inlet on the river, some 200m from the Irish Sea.

The extensive site was uncovered following an excavation by Archer Heritage Planning, directed by Dr Clinton in collaboration with archaeologist Mr Kelly and local historian Michael McKeown, under the aegis of the Annagassan and District Historical Society.

The discovery has caused excitement in Co Louth, with 30 visitors to the site yesterday.

Dr Clinton said the finds “will be conserved and analysed and a full report of the findings published”.