Irish archaeologists excavating a prehistoric tomb north of Dublin have discovered that ancient "vandals" left graffiti on the stonework, Environment Minister John Gormley said on Thursday.
Scientists have been working for almost 40 years to unlock the secrets of the megalithic tomb of Knowth in County Meath, believed to date back to about 3000 BC.
Gormley said that the names of 15 or 16 early "vandals" who had carved their names into the stones had been translated using ancient texts, quipping: "Some things never seem to change".
Knowth and a group of similar tombs in the area were built around the same time as Britain's Stonehenge and 500 years before Egypt's Great Pyramid of Giza and are one of Ireland's top tourist attractions.
They house a huge collection of Western European Neolithic art as well as the latest graffiti discovery.
Newgrange, the biggest tomb in the group at 13 metres high and believed to be the world's oldest continuously roofed building, is now open to the public.
On five days around the 21 December solstice the shortest day of the year in the Northern Hemisphere the sun shines deep into a tomb, flooding light into a chamber where the remains of the dead were once laid.