Ancient engineers made Newgrange
While the recent opening of the Dublin Port Tunnel has brought modern engineering feats to the forefront of many minds, kudos for Irish construction could go back much further. Back all the way to the Stone Age, in fact.
Take Newgrange, the most renowned of Ireland’s prehistoric sites. Newgrange is a large, man-made stone and turf mound burial chamber built sometime between 3300 AND 2900 BC, an astonishing 5,000 years ago. This makes it 600 years older than the pyramids at Giza in Egypt and 1,000 years older than Stonehenge.
Sitting atop an elongated ridge by a bend in the Boyne River about 10 kilometres west of Drogheda, legend has it that Newgrange is one of the Sidhe, or fairy-mounds, of Celtic mythology. However, the site was already about 2,000 years old at the dawn of the Celtic era.
Its antiquity aside, Newgrange is also famous for another thing, which only happens one day a year, on December 21, the winter solstice.
On that, the shortest day the year, as the sun rises above the horizon, its rays travel through a special opening above the main entrance and down 24 metres of stone passageway to illuminate the mound’s cross-shaped inner chamber for 17 minutes.
This precision in planning, placement and construction is simply astounding given that tools in the Stone Age were little more than chipped rocks. No metal or mortar of any kind was used.
In order for ancient engineers to position the monument correctly, they would have had to call upon astronomers to determine exactly where the sun would strike that day. This would have meant years of careful heavenly observation monitoring movement of the sun.
After the astronomers had done their job, the Stone Age version of geologists would have been called in. Newgrange’s designers needed rocks large enough to form the structure, strong enough to bear weight and malleable enough to be shaped as needed.
In fact, many of the megaliths, or giant stones, used to build Newgrange came from a site about 22 kilometres away and the outside of is faced white quartz and granite from the Mourne Mountains to the north and Wicklow Mountains in the south.
If at all unimpressed by prehistoric building methods, keep in mind that the roof of Newgrange has been intact and watertight for 5000 years and the passage, chamber, roof and kerb of 97 stones were all constructed without mortar. The entire mound contains about 200,000 tonnes of material, and it has been estimated construction would have taken about 30 years using a workforce of 300.
For more than 4,000 years Newgrange was hidden and lost to humanity until 1699, when landowner Charles Campbell sent his labourers out looking for building stone. They uncovered the site, thinking at first it was a cave.
Designated a World Heritage Site by the United Nations in 1993, Newgrange attracts 200,000 visitors each year.