Visited 2nd August 2004: Cliacabhaigh is on the grass verge to the east of the lane, usually obscured by farm machinery. I understand that this is not private land, but the local crofter is not at all keen on visitors.
When I visited I found the stone had been vandalised with yellow paint. Hand prints on the south size indicated that children had been involved. Unfortunately the farm machinery that has accumulated around the stone means that it would be easy to paint the stone without being seen from the lane. Having said that, the nearest croft is relatively nearby, and overlooks the stone.
Lining up the stone with the main Calanais site is interesting. There is certainly a relatively straight route between the two, marked by the modern lane. The only advantage of the yellow paint is that you can now just about make out Cliacabhaigh from the main site.
Despite being an obvious suspect, Cliacabhaigh was first recorded relatively recently in a 1976 edition of Discovery and Excavation in Scotland. It is not yet scheduled.
In the excellent book The Stones Around Callanish (ISBN: 0 903960 67 2) by the Pontings is a description of the stone and a pe-vanadlism photo. Margaret Curtis (née Ponting) interprets it as part of the complex, possibly serving a processional function:
...it is 800 metres from he central stone at the main site; at an azimuth of just 1 degree, it is very close to due north and is in direct line with the central megalith and the central row. As seen from this stone, the moon would have transited low over the horizon when at its southernmost extreme.
Margaret has identified two other stones nearby which may have once been standing. One is in the field wall, and the other lies on private land nearby, almost entirely covered in peat.