Whilst taking pictures of the SE circle my eye was drawn to this wonderful earth work just 75m away and up the hill a little. Upon investigation it turns out to be a massive henge 30m in diameter. I do not think it is a rath because there is a large entrance (4m wide) facing south east - the same orientation to the circles.
The banks are at least 1.3m high and the center is very boggy now. A great place.
The OS map has this monument marked as a barrow. If it is a barrow then it's a big one and, unusually, the bank and fosse around it have two opposing gaps. I still think this is a henge and that it was classified as a barrow, because no one expects a henge this far south, so therefore it can't be a henge.
It is actually just 50m or so from the stone circle. It is built on the top of the col between the two peaks that overlook the complex. This means that this is the only monument here that has views to the south. The terrain only allows the other monuments to look west.
I will not include directions for these sites. If you wish to find them then I recommend a good compass and an OS map. Even better a GPS.
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.