The Plain of Jars in Laos is strewn with giant stone vessels of unknown purpose

Scattered across the highlands of northeastern Laos are thousands of stone jars, some standing taller than a person and weighing as much as a small truck, grouped into clusters that range from a handful to several hundred at a single location. No one living has recorded who carved them, when the work began, or exactly what they were for. More than ninety years after the first scientific survey of the region, the jars that give the Xiangkhoang Plateau its name, the Plain of Jars, remain one of the least understood megalithic landscapes in Southeast Asia.

Thousands of Jars Spread Across Dozens of Sites

Surveys have identified more than 120 jar sites across Xiangkhouang Province and its surroundings, with 129 now confirmed through recent fieldwork. UNESCO officially recognizes just over 50 of them, and documented sites contain more than 2,100 individual jars in total. Most stand between one and three meters tall, cylindrical in shape and wider at the base than at the rim, and all were hewn directly from bedrock rather than assembled from smaller pieces. Toolmakers worked with whatever stone was locally available, including sandstone, granite, conglomerate, limestone, and breccia, and some of the heaviest examples weigh as much as 14 tons. The largest known concentration, Site 52, holds 392 jars near a Hmong village reachable only on foot, while the most studied and most visited location, Site 1, sits close to the modern town of Phonsavan.

The Evidence Points to Burial, Not Storage

French researcher Madeleine Colani led the first serious excavations in the 1930s and concluded the jars were tied to funerary practice, a theory later fieldwork by Lao and Japanese archaeologists has reinforced. Inside several jars she found colored glass beads mixed with burnt teeth and bone fragments, while unburned secondary burial bones, pottery, and bronze and iron objects turned up in the ground surrounding them. Roughly 200 carved stone discs have also been found near the jars, and researchers now suspect they served as grave markers rather than lids, since none has ever been found sitting atop a jar or shaped to fit one. A handful of discs carry carved imagery, including a “frogman” figure at Site 1 and animal designs such as tigers and monkeys. Luminescence testing has dated some jars to as early as 1240 to 660 BC, though excavations focused on the burials themselves point to continued use for secondary burial as late as the eighth through thirteenth centuries CE. Separate geological testing traced the stone used at Site 1 to a quarry roughly eight kilometers away, underscoring the scale of labor required just to move the material before any carving began.

A 2026 Excavation Fills a Long-Standing Gap

Fieldwork at Site 75 in 2026 uncovered a jar, cataloged as Jar 1, that measured about 1.3 meters high and more than two meters wide and still contained the remains of at least 37 people, dated between 890 and 1160 CE. It marked the first jar found in the region with undisturbed human remains preserved inside the vessel itself, rather than in the surrounding soil. Analysis of the bones and teeth suggested the jar was reused across several generations as part of a secondary burial tradition, in which remains were placed inside only after earlier stages of mortuary treatment elsewhere. Glass beads and other objects recovered alongside the bones point to ongoing ritual or commemorative activity tied to the burial process, adding physical evidence to a funerary theory that had rested mostly on circumstantial finds around the jars rather than inside them.

Local Legends Tell a Different Story

Long before archaeologists arrived, communities around the plateau explained the jars through the story of Khun Cheung, a king of giants who supposedly ruled the region after defeating a rival king named Chao Angka. According to the legend, Khun Cheung had the massive jars made to brew and store rice wine, known locally as lau hai, to celebrate the victory, with the largest jar set aside for himself. A separate strand of local folklore holds that the jars were not carved at all but molded from a mixture of clay, sand, sugar, and animal products, a claim archaeological analysis of the stone itself does not support.

A War Left Much of the Site Unexamined

Between 1964 and 1969, the United States Air Force dropped an estimated 270 million cluster submunitions on the Xiangkhoang Plateau while targeting North Vietnamese and Pathet Lao forces during the wider conflict in Laos. Roughly 80 million of those bomblets failed to detonate, leaving unexploded ordnance scattered across jar sites for decades. Clearance work led by the Mines Advisory Group, coordinated with UNESCO and funded by the New Zealand government, cleared the three most visited sites between 2004 and 2005, with additional clearance in 2007 opening four more locations to visitors. Even with that progress, less than ten percent of the known jars have been thoroughly studied, because unexploded munitions still make large sections of the plateau too dangerous to excavate. Additional background on the site’s excavation history and dating is available through Wikipedia’s entry on the Plain of Jars.

This article was produced with the assistance of AI and reviewed by Morning Overview editors prior to publication.

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