There's a concentration of prehistoric sites in the south western Ireland and in the North, though the largest structures are to be found elsewhere - Newgrange in Co Meath by the Boyne River is a fabulous complex of passage tombs, and the stupendous size of the Lios Grange stone circle/henge has to be seen to be believed.
Co Kerry is home to some small but perfectly formed small stone circles such as the delightful Lissyviggeen just outside the popular tourist base of Killarney, and Kenmare, just a few hundred yards walk from the town centre. The mighty Eightercua alignment (top left) is also found in Kerry, on a ridge overlooking the water.
The richest collection of prehistoric stones is to be found in Co Cork, particularly in the region around Macroom. Stone circles in this region include the attractive triangular stones of Ardgroom, with their breathtaking views of the valley beyond, Glantane and Knocknakilla, each featuring a singular tall stone heading the ring. These sites are feature of a megalithic countryside of countless standing stones and many alignments all around.