Actun Tunichil Muknal is a cave in Belize, near San Ignacio Cayo, notable as a Maya archaeological site that includes skeletons, ceramics, and stoneware. The most famous of the human remains is known as "The Crystal Maiden", the skeleton of a teenage girl, probably a sacrifice victim, whose bones which have been completely calcified by the natural processes of the cave, leaving them with a sparkling crystallized appearance. There are several areas of skeletal remains in the main chamber.