As you walk across the field towards this large portal tomb, the scale of its largeness becomes increasingly apparent. The capstone rises some 3m from the ground and rests on two of the most balanced portal stones I have seen. These are shaped so that they reach a fine point in profile on which the capstone rests.
The chamber is half full of cairn material, which almost reaches the top of the cute half height door stone. 2m long slabs form the side walls of the chamber, the rear of which is over-grown by the hedgerow, because this tomb unfortunately stands in a field boundary.
I found a small piece of chalk not too far from the monument, which is interesting because the nearest source is some 20 miles north in Antrim.
I don't get up to this part of the country very often so I had to sieze the chance to visit Greengraves while I was here. I am so glad I did, because for the first time in a long time it has been cleared of all the gorse bushes that used to mask the front. For the first time I actually saw the portal properly. Although oddly one little whisp of gorse has been left standing next to one of the portal stones .
I wish that this magnificent monument could be liberated completely from its hedgerow prison, but I cannot see it ever happening. It would be really good to be able to walk all the way around it and see it properly from every angle.
Portal stones are a pair of upright stones that form the 'entrance' to a portal tomb. They are usually well matched, being of even dimensions. As well as forming this doorway they also act as the front support for the capstone and are usually taller than the stones that form the chamber.
Often there is a door stone in between them blocking off access to the chamber within.
Although this is nearer to Dundonald it is best to give directions from Comber. Head north on the A22 from Comber for 4km, almost into Dundonald. Turn left here and take the next right hand turn you come to. After just under 1.5km there is a track to the left. The tomb is in the field just beyond this track.
This is an explanation of (and a bit of a disclaimer for) the coordinates I provide.
Where a GPS figure is given this is the master for all other coordinates. According to my Garmin these are quite accurate.
Where there is no GPS figure the 6 figure grid reference is master for the others. This may not be very accurate as it could have come from the OS maps and could have been read by eye. Consequently, all other cordinates are going to have inaccuracies.
The calculation of Longitude and Latitude uses an algorithm that is not 100% accurate. The long/lat figures are used as a basis for calculating the UTM & ITM coordinates. Consequently, UTM & ITM coordinates are slightly out.
UTM is a global coordinate system - Universal Transverse Mercator - that is at the core of the GPS system.
ITM is the new coordinate system - Irish Transverse Mercator - that is more accurate and more GPS friendly than the Irish Grid Reference system. This will be used on the next generation of Irish OS maps.