A cairn is a man-made pile or stack of stones, often used as a landmark or a memorial marker. Cairns have been constructed by various cultures throughout history and can be found in different landscapes, including mountains, deserts, and coastal areas. In ancient times, cairns were utilized for various purposes, such as indicating trails, marking burial sites, or serving as religious or ceremonial structures. They were particularly important in prehistoric societies, where they played a vital role in navigation and ritual practices. Cairns vary in size and complexity, from small single-stack markers to large and elaborate structures. In modern times, cairns continue to be used for navigation and as memorials or monuments, blending traditional and contemporary cultural significance. Cairns also hold ecological importance, as excessive or inappropriate construction can disturb the natural landscape and impact ecosystems. Properly understanding and respecting the cultural and environmental context of cairns is essential for preserving these significant human-made features across the world.