Newgrange is circular, with a flattened front. Its average diameter is 103.6 metres, or 113 yards. (These are O’Kelly’s drawings, gratefully borrowed, as all the information on these and other pages is borrowed, from books by O’Kelly and by other writers.)
The interior passage (the cruciform shape in the lower right quadrant of the drawing above) is 18.95 m (20.7 yards). The passage is formed by 22 standing stones, called orthostats, on the left side, 21 on the right. (See the drawing below.) The passage ends in a chamber with three recesses and a domed ceiling 20 feet high.
There are 97 sandstone kerbstones, averaging roughly 6 feet by 3 feet and about a ton in weight, placed so that their tops are exactly three feet above the ground. The kerbstones were quarried from Clogher Head, near the mouth of the Boyne, about six miles from the site. They were transported by water, perhaps by being strapped to canoes that were lifted by rising tides in the River Boyne estuary.
The bright white stones at the front of the tomb are quartz, from the Wicklow Mountains, 80 miles away to the south. O’Kelly found them collapsed on the ground at the front of the tomb, but conjectured that they had been intended to be part of a nearly vertical wall. To accomplish this in his reconstruction he had to use reinforced concrete. A very good book, Newgrange, by Geraldine Stout and Matthew Stout, husband and wife archeologists, states: “It was the last time in Ireland that scientific opinion, no matter how well founded, and a modern esthetic would be allowed to impinge so forcefully on the ancient. If it were done again, the current approach to the presentation of ancient monuments would have seen Newgrange restored as unobtrusively as possible; accessible, yes, but a ruin…As an approach to interpretive reconstruction, new Newgrange is itself a monument to past standards. It stands at the end of a tradition of an intrusive style of presenting ancient monuments throughout the world…It has been included in an international list of the world’s worse archeological reconstructions.”
Newgrange was built over several generations, at a time when the average age for men was 28, for women 25. The people who built it were neolithic or megalithic hunter-gatherers. (Neolithic means new stone, megalithic large stone.) They developed farming around 4000 BCE and by 3000 BCE were well fed and had the time and the reserves of food to look beyond their day-to-day survival. They were sufficiently wealthy that large areas of turf could be permanently removed from farming. This compromised the fertility of the land. Thus Newgrange was both the apogee of this prehistoric civilization and the origin of its demise.