Perhaps, like the other similar structure at Ballyward this is a hut site too, but this one really makes me doubt it. As well as the bank with stones lining the outside and inside there is a third ring of stones in the centre, 60cm from the bank. Within this there is a definite mound that has been dug away in one corner.
These two sites are a real mystery, but I will find out more.
Take the N81 south from Dublin and turn left at the Kilbride junction along the R759. Continue through Kilbride and on for another 4.5km where you will find a road to the right. Take this and then at the next junction go right again. 1km along this road you will reach atrack on the right that leads upto Ballyward woods. Park near the gate and enter the woods. Take the left track and continue around the woods always bearing right. You will pass a ruined cottage and a track to the left. In the next field after the track you will see two stone features. This is the furthest one from you.
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.