Although Newgrange is just one of many important monuments dating back to the Neolithic period within the Brú na Bóinne complex in County Meath, it is without question the most famous. Believed to be older than both England’s Stonehenge ring of standing stones and the ancient Egyptian pyramids, this 76-metre-wide circular mound contains an interior passage that stretches nearly 20 metres into its centre, reaching a chamber with a corbelled vault roof.
Though the function of Newgrange has been debated among academics, a majority of archaeologists believe it was of religious import, relating to respecting the dead. It is generally accepted that this main inner chamber was originally used as a burial tomb – and this is where the magic happens in winter. The talented late-Stone Age builders of Newgrange were able to design it so that on the shortest day of the year, light from the rising sun would align precisely with a specifically designed roof box above the passage entrance.
Thanks to this deft angling, the winter solstice sunrise is able to shine through the roof box and directly down the passage into the central chamber for around 17 minutes. There, it lands on the chamber floor and illuminates the wall carvings such as the pre-Celtic triple spiral within. Although light hits the chamber around four minutes after sunrise today, calculations have shown that at the time of building, the first light would have flooded it the moment the sun came up.
Seeing the light enter the Newgrange chamber is a once-in-a-lifetime experience, for which crowds gather outside its entrance early in the morning every December 21st without fail. Of these crowds, a lucky few have been chosen by lottery ahead of time to enter the chamber along with a guest to witness the phenomenon, weather permitting, of course – in 2015, heavy rain kept the dawn sunlight from entering at all.