I first read of this site in Anthony Weir's guide book - Early Ireland. He states that he only included it because it is easy to get to (which is true), but that it is not a nice tomb - surely it can't be that bad! So, I decided to make quite a detour to see ... and it is! It's horrible.
I think that the location really doesn't help, being next to a road and next to a barn and next to a wall. The rear of the tomb, which is made from great nobbly slabs, has collapsed, but the front is in good condition. A large roof stone rest on 1.7m tall walls, creating quite a large chamber. However, a wall has been built right up to the front of the tomb, making it impossible to really see well.
If it was in a field, on a hill this would be a great tomb, but stuck where it is? No. It's worth a stop if you're passing, but don't go too far out of you way.
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.