This is one of the largest capstones I have ever seen and unsurprisingly one of the flattest portal tombs that I have ever seen. The capstone measures a whopping 5m x 4m and 1.5m think in places. As you approach it from the road its size becomes more and more daunting.
Compared with the scale of the capstone the main structure was tiny. There was no way that this could have stayed up for long without some support of a cairn, traces of which can be clearly seen in the surrounding boggy ground.
I couldn't make head-nor-tail of the collapsed stones, but apparently the portal stones are 2.4m tall, which means that the structure would have reached a very tall 4m+. This is definitely a tomb that it is a shame to have 'lost'.
Boulder burials are very simple, yet striking monuments. As the name suggest they are simply burials beneath a large boulder. The burials contained within are mainly single and set in a small kist like chamber made from smaller stones (see Reanacaheragh (County Cork).
Boulder burials can be found on their own or within or around stone circles. The boulders often bear cup marks and were often picked for their curiously attractive shape or rock patterns.
Two stones place either side of a gallery, opposite each other, but not touching so as to leave a gap, that are used to segment it into smaller chambers.
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.