Most simply, a cairn is a pile of stones. Hikers are familiar with them on the trail. Other hikers place stones marking the path in places where it may get confusing about where to take the next step, either in wide open spaces, or to mark a place where the path turns. Cairns also mark ancient burial sites, or sacred places. Cairns are primal, timeless markers. For me, and for this blog, as a metaphor, cairns let you know that you are in the right place at the right time.
Caravans and Cairns 