The “Plain of Jars” in Laos has both fascinated and mystified archaeologists and historians alike since it was first recorded in the scientific literature in the 1930s. For centuries, hundreds of large stone jars have contained the interred bodies of ancient societies – but how they got there and what happened remained a mystery. Now, researchers excavating the jars are beginning to piece together the megalithic puzzle.
"The sites are mesmerizing; they are the ritual remains of a unique culture that has long disappeared," study author Louise Shewan, from the University of Melbourne, told IFLScience. "It is at first the sheer physicality and beauty of the megaliths dotted across the landscape that captivates the visitor, and when you consider the effort and skill required to carve them and to move them several kilometers from the quarry locations to their final resting places, it is a huge investment of time, skill and organization."
Plus, there is so much still to learn. A recent excavation of Site 1 at Bang Ang, which contains nearly 400 jars, suggests that burial jars in the area may in fact number in the thousands. Here, they found evidence of high rates of infant and child mortality, possibly from a malnutrition or disease event that struck the growing population. Researchers found that the cemetery was used for all ages and both sexes. More than 60 percent of the 18 individuals documented were infants or children, almost half of which had died at the fetal stage or in early infancy. Four of those individuals also had dental enamel hypoplasia, an indication of growth disruption possibly from poor nutrition or disease.
"From our excavations at Site 1, we have identified three types of mortuary ritual practice: secondary burial of human bone, secondary burial of human remains in buried ceramic jars and, for the first time, a primary burial of two individuals," said Shewan.

Published in Antiquity, the research confirms earlier findings of other excavated sites. Here, sandstone “pavements” were laid around the jars with secondary burials and interments placed inside the ceramic vessels. Researchers also found a pendent and glass beads, as well as small ceramic vessels and ear discs that were found at previous sites. But that’s where the similarities end. The special mortuary practice employed at the Plain of Jars is distinct from other jar burials found in Southeast Asia, which contain a wide range of material culture including jewelry and goods made from iron, bronze, and stone.
"Site 1 is of major ritual significance and has been for a very long time. We, however, know very little about the culture that created the jars and this is one of our main research interests," said Shewan. "We do not as yet know when the jars were placed on the landscape and if indeed the burials around them are contemporaneous with the jars or how they are related to each other."
Although radiocarbon dating of other sites ranges from 8200 BCE to 1200 CE, the Plain of Jars site is much more recent and was likely established between the 10th and 13th centuries. Earlier this year, more than 100 of the 1,000-year-old massive stone jars were discovered across 15 sites in Laos. Shewan says that the team will excavate another site in the region and continue analyses of the jars themselves in an effort to learn more about the ancient civilization responsible for the burial site.
