Cairn

A cairn () is a human-made pile (or stack) of stones raised for a purpose, usually as a marker or as a burial mound. The word cairn comes from the Irish: carn [ˈkʰaːrˠn̪ˠ] (plural cairn [ˈkʰaːrˠɲ]). Cairns have been and are used for a broad variety of purposes. In prehistory, they were raised as markers, as memorials and as burial monuments, some of which contained chambers. In the modern era, cairns are often raised as landmarks, especially to mark the summits of mountains, and as trail markers. They vary in size from small piles of stones to entire artificial hills, and in complexity from loose conical rock piles to elaborate megalithic structures. Cairns may be painted or otherwise decorated, whether for increased visibility or for religious reasons.