Laois Gardaí are investigating incidents of criminal damage to one of the county's most popular historic landmarks and tourist attractions.
Gardaí are investigating damage caused to the Rock of Dunamase after graffiti was sprayed on a number of points on the historic walls within the last two weeks.
Gardaí are appealing to anyone who may recognise the 'tags' or initials that have been sprayed on the walls including 'DREVM' and 'SSG'.
Anyone with information is urged to contact Portlaoise Garda Station 057 86 74100.
The Rock of Dunamase is located off the N80 between Portlaoise and Stradbally.
Excavations in the 1990s demonstrated that the Rock was first settled in the 9th century when a hill fort or dún was constructed on the site. The castle was built in the second half of the 12th century.