Manx National Heritage has reacted with shock after discovering vandals spray painted graffiti over the monument at Hango Hill.
A spokesperson said: “We are shocked and disappointed that this important historic site has been vandalised and have reported the incident to the Isle of Man Constabulary.”
It is a criminal offence to damage an ancient monument.
“We are currently assessing the damage and will determine the most appropriate approach to restoring the monument,” the spokesperson said.
Place of Execution
Hango Hill, near King William’s College, is a Bronze Age burial mound and was a place of execution during the Viking Age – hence its Norse name which means ‘hanging hill’.
It is best known as the site of the execution of Illiam Dhone in 1663.
The spokesperson said: “The remains of a post-medieval summerhouse stand on the top of the hill and the walls have been extensively spray-painted.”
MNH appeals for witnesses, or anyone with information that may identify the culprits, to contact the police.