Humans have been stacking stones for an awfully long time. England’s Stonehenge was thought to be used as a burial site, and created as early as 2500BC. Inuksuks, made by the inhabitants of the Arctic region, were used as markers for travel routes and hunting grounds. Cairns have been found in Scandinavia as trail and sea marks, and in Somalia, to indicate tombs of former kings. Modern cairns are commonly used to indicate hiking trails, biking trails, or areas of possible danger. And some very patient people have even transformed rock balancing into performance art. These man-made stacks of stones and delicately balanced sculptures are truly fascinating things of beauty.