Workmen carrying out roadworks near the Caha Mountains, right on the Cork-Kerry border, have uncovered an underground passageway believed to be about 1000 years old.
The structure, called a ‘souterrain’, appears to have been tunnelled into rock overlooking the Sheen Valley.
Archaeologists have now said the site is to be sealed and preserved.
These type of structures were usually utilized for shelter and food storage.