Four mighty stones stand like sentinels before it. The largest of them is eight or nine feet high above the ground and at least twenty in girth; and they are all that are left of a ring of thirty-five similar monsters which once guarded the great cairn with a circle a quarter of a mile around.
The huge passage-grave at Newgrange is surrounded by an enormous stone circle, one of the largest
in Ireland, with a diameter of 104 meters. The circle was long considered to date from the neolithic and to be contemporary with the great cairn it surrounds. In the narrative constructed by the main excavator between 1962 and 1975, Michael O'Kelly, the late neolithic / early bronze age people at Newgrange were squatters. O'Kelly liked to view the monument as a purely neolithic site, uncontaminated by later incursions like those at Knowth and Dowth. In the early 1980's research and excavation at Newgrange by David Sweetman demonstrated an intense level of ritual activity in the forecourt at Newgrange circle, firmly dated to the bronze age drawing the age of the Great Circle into question.
There are twelve standing stones remaining today, the same number that was reported when the mound was first recorded in 1699. There is an average of nine meters between the surviving stones,
which means that if the circle were ever complete, it could have contained
up to thirty-six stones.
The largest and tallest stones are found in the area facing the Entrance, creating a kind of forecourt or defined space. American researcher Martin Brennan was first to discover that several of these stones cast shadows at sunrise and sunset, which interact with carvings on the kerbstones.
Professor Michael O'Kelly suggested that the stones used for the Great Circle were left-overs from the megalithic phase which had been too large to use in the construction of the main monument. In his written work O'Kelly tends to view Newgrange as a 'pure' site, uncontaminated by later activities, and perhaps he is insisting that the circle is neolithic in an attempt to draw attention away from bronze age 'squatters' who left hearths, postholes and a huge timber 'Woodhenge' close to Newgrange.
Due to the composition of the layers uncovered during the excavations we know
that the circle was built long after the main mound was completed but before
the cairn collapsed. Several of the standing stones were snapped at their
base, but had no cairn-slip under them, indicating that they may have been broken by some massive event.
Excavations
The excavations undertaken by David Sweetman in the 1980's seemed to prove that the stone circle was built after the great Bronze age Woodhenge to the east of Newgrange. It seems likely that the circle is a Bronze age addition and is several hundreds of years younger than the massive passage-grave and probably the last monumental construction on the site. The circle tells us that Newgrange and its environs were still held in great esteem a thousand years after the mound was constructed.
Interestingly, the Great Circle has the same diameter as the two inner circles within the massive ring at Avebury
in England. Of the twelve remaining Circle stones at Newgrange, the four largest and most imposing
are on the south east side before the entrance. These stones are 2.5 to
3 meters tall and weigh many tons. Perhaps they were erected at the same time as the Avebury circles.
Excavations have revealed that GC9, the strange conglomorate stone illustrated at the top of the page, was surrounded by some kind of timber structure during the bronze age. Two parallel rows of post holes, which held huge timber posts, burned down or was set on fire; the heat was so intense that the stone was cracked and damaged.
The stone above, GC-10 had fallen when the mound collapsed and was found lying flat. Macalistar and Praeger examined
this stone and had a pit dug under it to view the lower surface in June
1928. The pit was covered with planks and left that way until O'Riordain
looked at it in 1954. He noted that there was no cairn slip beneath the
stone and uncovered the socket and packing stones 7 meters from the kerbstones.
During O'Kelly's excavations in 1973 GC-10 was examined and restored to upright.