That one in the picture is a modern one, probably. I'm not going to get into how I tell them apart.

The old curricks are interchangeable with standing stones - to which they are related by function. The most known in one place is *nine*. They are intended to be viewed from a specific site against the horizon. When there is more than one in a line then they were presumably to distinguish between sunsets, or similar, from one day to another. As they are constructed of drystone they can be simply moved to finely tune the azimuth they describe. Then there are keepers and walkers' cairns. They can be distinguished by style, given about fifteen or twenty years practise. The real ones very usually are found associated with megalithic sites. Sometimes they are the only bits of these monuments that remain.

Have you seen the stars tonight ? Mars, Moon, Venus, with Castor and Pollux.