Newgrange (Brú na Bóinne), situated in the Boyne valley is Ireland's best known example of a Passage Grave. It is a hugh earthen mound pierced by a long narrow passage, wide enough for 2-3 people. The tumulus, or main mound, is surrounded by a shallow ditch, now grassed over, with a number of the original pillar stones in place. A kerb of 97 huge stones (many with spiral motifs) supports a dry wall. The threshold stone is carved with a triple spiral, circles and diamonds which can be clearly made out.
The central passageway is narrow and low and the central chamber now artificially lit for tourist parties, however on the Winter Solstice (21 December), a shaft of light enters the passage at dawn and for a few minutes strikes the centre of the floor illuminating the chamber.
Some estimates of the mound's age have placed it at over 5000 years ago, which makes it several hundred years before the construction of first Egyptian pyramids or the Stonehenge. The mound you can now visit, however, has been mostly reconstructed, including an outer facade of white quartz which doesn't quite ring true.
Around 20 people can be taken into the passage and central grave in each group, and the Solstice visits tend to be booked up to 4 years in advance.