This famous site is said to be able to determine the dates of winter and summer solstices – see the Megalithic Sites link for a full description.
Access to the site is by the track off the A83 at NR730527. There is limited parking here but ample about 0.25 mile further south where the road crosses the Ballochroy Burn. The people in the Balochroy bungalow near this parking point do not own the land on which the stones stand but they thought getting permission was unnecessary.