As you enter the visitor's centre car park for the eclesiastical and walk around the churches you can not fail to notice the precarious ruins of this castle a few hundred metres away. Crossing the field to see it reveals just how insanely balanced the ruins are.
Obviously built to command traffic along the Shannon the castle occupies a superb location. The motte is 15m above the bottom of the ditch around it, which in places is surrounded by a bank of equal height. The bailey extends towards the river and is also raised to a height of 10m above the river.
Walking to the west side around the high bank allows you to see the better part of the ruins. From this side a bit more (but not a lot) of structure can be seen. Certainly the most impressive part of the castle is the huge ditch and the location.
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.