This 3000 year old stone stands 2.25m high and has a carefully carved round hole running through it. The hole is 13cm in diameter at its largest and 12cm deep. According to local historian Jack Sheehan, "It's a marriage stone.  The hole in the stone is narrow on one side and wide at the other. The man had a bigger hand and he put his hand through the big side and the woman put her hand through the narrow side.  They made their promises when they put their hands through the stone."
External Links:
https://roaringwaterjournal.com/tag/caherurlagh-holed-stone/