This stone is the Lia Fail or 'Stone of Destiny' at the ancient Irish seat of the high kings at Tara and it is said that the stone would roar when a righteous King touched it.
The famous decorated kerbstone and entrance to the neolithic passage tomb of Newgrange, Co.Meath, Ireland. The site predates the pyramids of Egypt and was built with a sophisticated understanding of astronomy. On the Winter Solstice each year, the morning sunlight enters through the lightbox that you can see above the doorway, and fills the underground inner chamber with light for a few minutes.
It is a truly magical place. I have been inside the chamber of Newgrange with a group of fellow tourists on two occasions and experienced a simulation of the winter solstice light entering the inner chamber. I found even the simulation to be a very emotional experience and always fill in several entries to the lottery to actually be one of the lucky few to be there for the Solstice.
My Mum and Dad are currently on an amazing trip to Peru and are visiting the sites of another Sun worshipping people, including of course Machu Picchu which also has a stone which aligns to the Winter Solstice. The mind boggles to think of the grasp of astronomy that Newgrange's builders had in an age that didn't even have the wheel. We can learn a lot from these mysterious peoples.
A look in to a passage tomb at nearby Knowth. The passages were built on the ground and then had a mound of earth put over it and often carved kerbstones were placed around the outside.
If you live in Ireland and have never been to visit this special place then I suggest you remedy that situation post haste!