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View of Cairn H from the west side. The mound was excavated by Joseph Raftery in 1943.

Loughcrew - Cairn H

Cairn H is, in some respects, one of the most interesting of the cairns at Loughcrew. The monument has a typical cruciform chamber constructed within a kerbed mound of about sixteen meters in diameter. There are some beautifully executed megalithic art within the chamber: a set of three spirals on the sillstone covering the entrance to the right-hand recess, seems to anticipate the Entrance Stone at Newgrange.

The chamber of Cairn H.
Looking south across the chamber of Cairn H from the right-hand recess.

Eugene Conwell, a local school teacher, excavated Cairn H in 1865, and made many finds, both from the neolithic and from a much later period of reuse during the Iron age. He came back again in 1868 to resieve his spoil from the dig. You can read Conwell's excavation which lists his finds on the following page.

Raftery Excavations 

In 1943 Joseph Raftery of the National museum excavated the monument, and his finds ( which are still unpublished ) led him to conclude that this monument was, in fact, constructed in the Iron Age, mainly because he found many more carved bone slips at the foundation levels.

Excavations at Cairn H by Joseph Raftery.
Excavations at Cairn H by Joseph Raftery in 1943 turned up hundreds of bone slips carved during the Iron and medieval ages.
Cairn I at Loughcrew photographed by W. A. Green. The mound of Cairn H is visible about 200 meters away.
Cairn I at Loughcrew photographed by W. A. Green. The mound of Cairn H is visible about 200 meters away. Photo © NMNI; color added by the Fr. O'Flanagan History Group.

New radiocarbon dates from Loughcrew

The most famous artefacts uncovered at the Loughcrew megalithic cemetery in Co. Meath, Ireland, are the over 4,000 cattle bone slips that were discovered during excavations of Cairn H by Eugene Conwell in the 1860s and Joseph Raftery in 1943. These bone flakes were retrieved from the sockets of two different orthostats and may represent 500 to 600 original pieces, 150 of which were decorated with La Tène style carvings.

It is the intricate carvings on these highly-polished and carefully-worked slips that have attracted particular interest. Thirteen of the flakes appear to have originally formed part of bone combs; however, the use of these combs and the function of the rest of the flakes remain unclear.

Somehave argued that the bone flakes may have been trial pieces belonging to a bronze smith, knives accompanying burials in the tomb, or the remains of a Celtic craftsman’s workshop. It has also been suggested that the flakes served a ritual purpose and that their deposition within the tomb was associated with Iron Age ritual activity at the site.

The combination of the Iron Age-style carvings and the stratigraphic evidence led Joseph Raftery to argue that Cairn H must itself have been constructed in the Iron Age. However, the Neolithic and Early Bronze Age deposits found within the tomb make this exceedingly unlikely, and it is now generally agreed that the finds represent subsequent activity during the Iron Age.

Though we may never know for certain what motivated the burial of these bone slips or why they were carved in the first place, the other artefactual evidence from the tomb does indicate a Neolithic construction date for Cairn H. This was later followed either by the intentional disturbance of the tomb and its orthostats, or by an unintended partial collapse of the structure. The carved slips would then have been placed within the orthostat sockets, after which the orthostats would have been reset in place.

Mara Vejby 

The chamber of Cairn H.
Megalithic spirals on the sillstone blocking the right-hand recess within the chamber of Cairn H.


Martin Brennan's research demonstrated that most of the functioning Loughcrew cairns express interest in astronomical events. Brennan found that the axis of Cairn H is oriented to a sunrise in the south-east about a month after the Autumn equinox, signalling that the November cross quarter day is approaching.

Some two weeks before Samhain (the original, ancient Halloween), the sun illuminates the panel at the back of Cairn H before moving into the chamber of Cairn L next door. It goes without saying that the movements and cycles of the moon can also be studied from this suite of monuments.

Looking out from the chamber of Cairn H along the passage.

Human remains

Conwell records two fairly extensive investigations of the monument: the first in September 1865, when the passage and chamber were dug out. The second visit took place in June I868, when the spoil-heap of the earlier excavation was carefully sifted.

From the passage and crypts of this cairn we collected, and have preserved for anatomical examination a large trunk full of human bones, many in a charred state, and apparently having belonged to individuals of various ages and sexes.

A deposit of bones, three feet thick, in a fragmentary state, nearly all showing evidences of having been burnt, was found in the passage. Mixed in with this deposit were several pieces of white quartz. The right-hand recess contains a stone basin.

Autumn equinox sunrise viewed from Cairn H.
Autumn equinox sunrise viewed from Cairn H.