Hill O’ Many Stanes, Caithness, is the best preserved and most dramatic of the multiple stone rows.
Twenty nine multiple rows are currently recorded in Great Britain. They all include at least four lines of stones. Most are “fan-shaped” in form although some consist of parallel rows of stones. The great majority (22) are in Northern Scotland and the remainder are in the Western Isles, Wales, Exmoor and Dartmoor. An article looking at the distribution of multiple stone rows is now available here.
Distribution of multiple rows. There is an obvious cluster in Northern Scotland.
The Stone Rows of Great Britain 
What do you think was its purpose?
Variations in magnetic north?
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Many thanks for the question, suggestion and your shared interest in stone rows. I think that we can be confident that all the rows denote places of importance, but establishing purpose is a whole load more problematic. The considerable variations between the different types of rows suggest that they may have had different, but perhaps related purposes. They all seem to share a preference for locations with particular visual links, although perhaps further work will reveal that this is not quite as straight forward as it currently seems. Regarding the idea of magnetic variations that might work for some, but the varied orientation of the multiple rows suggests that as a whole this is unlikely. The fan type rows are really only found in the far north of the Scottish mainland and this would seem to support the idea that they were being used for a particular local purpose. A purpose that never caught on elsewhere. The regional differences between the rows does support the idea of different groups (the term tribes would have been used in the olden days) that did things differently. The modern parallels for differences in religious beliefs and practices between regions probably provides an insight into what was going on.
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