Now, we really could not work these stones out. As you approach you can see two huge stone fairly close together and a smaller one some distance away and you assume it's a stone row. When you reach them you can see that the two large stones are not aligned in the same direction, nor do they suggest the entrance to a tomb.
The two taller stones are very well matched each standing 1.8m tall and 1.5m apart. The smaller stone is just 80cm high and is at a distance of 5m away from the two others.
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.