What were your ancestors doing in Ireland on May 1 in the year 4,000 B.C.?

If they inhabited an area in the present-day county of Meath they were building a passage tomb, a tomb that only came to light forty years ago in 1962.

It has taken those forty years to probe its secrets, and is only now being made accessible to the public.

It is located adjacent to a better known section of the prehistoric Knowth burial mound, and was discovered by Professor George Eoghan. Since then it has proven to be an archaeological find of the greatest importance.

Commenting on discoveries made within the past three years Professor Eoghan has said: "We literally dug out of the soil an art gallery of 350 decorated stones. This is by far the greatest collection of megalithic art in all of Europe and it bypasses the megalithic art found in the Iberian Peninsula and Brittany."

It will take years to analyse, and publish studies being undertaken of the messages contained on the decorated stones.

What your ancestors were doing in Ireland on May 2 in the year 4,000 B.C. is another story.