The Cairn reference article from the English Wikipedia on 24-Apr-2004
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Cairn

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A cairn is a pile of stones.

Typically, a cairn is used as a monument, to mark a path or to designate the summit of a hill. These present-day traditions emerged from the Bronze Age habit of putting cists into cairns, which would be situated in conspicuous positions, often on the skyline above the village of the deceased.

See also