Plain of Jars

← Encyclopedia

They sit in the long grass in their hundreds, mouths open to the weather, hewn from sandstone and granite and conglomerate and a hard, calcified coral-limestone — stone cylinders the height of a standing person, some narrowing toward a rim once closed by a disc of the same rock. The largest weigh as much as fourteen tons. They are not arranged in rows or rings; they cluster on knolls and saddles across the rolling uplands, a few here, more than four hundred there, scattered over a plateau that takes a full day to cross. The Xiangkhouang Plateau in northern Laos holds the densest concentration of carved stone vessels known anywhere on earth, and for the better part of a century the central facts about them — who cut them, when, and to hold what — have resisted a clean answer. What is no longer in doubt is that they are graves.

Carved stone jars standing in the grassland of the Xiangkhouang Plateau, northern Laos — Adam63 (Adam Jones), via Wikimedia Commons (CC BY-SA 3.0)

A field of stone vessels

More than 2,100 jars are cataloged across the inscribed sites, and the number keeps rising; survey in 2020 alone added twenty-seven previously unrecorded fields, lifting the Lao government’s register from roughly 100 to 127. Many more almost certainly stand hidden under forest and grass. The vessels are tubular, sometimes barrel-bellied, their interiors hollowed by hand and tool, their walls left thick. A minority were finished with a carved lip to seat a lid; loose stone discs lie among them, distinct from the lids — flat-faced, set into the ground as markers over the burials around the jars rather than placed atop them.

A cluster of the tubular, hand-hollowed stone vessels, some narrowing toward a carved rim — Artix Kreiger, from Flickr, via Wikimedia Commons (CC BY 2.0)

The stone is not local to every site. Detrital-zircon geochronology has tracked the granite of the jars at the most-visited field, Site 1, to a quarry roughly eight kilometers off; stone for jars elsewhere came from an outcrop nearly a hundred kilometers distant. At the quarries themselves, unfinished jars remain in situ, abandoned at every stage of the work — blocks scored from the bedrock, roughed cylinders, vessels nearly hollowed — a frozen production line that shows the jars were quarried, shaped on the spot, and then hauled, fully or partly formed, across broken country to the burial grounds. Moving a fourteen-ton monolith over those ridges was not the work of a family. It implies a society able to command labor, route it, feed it, and repeat the feat thousands of times. The jars are, before anything else, a record of organization.

A few carry marks. One jar at Site 1 bears a human figure in low relief, arms and legs splayed in the posture conventionally called the “frogman,” a motif echoed in rock paintings far to the northeast at Huashan in Guangxi. At Ban Phakeo, lids carry bas-reliefs read as monkeys, tigers, and frogs. These are the exceptions; the overwhelming majority of the stone is unornamented, its expressiveness entirely in mass and silhouette.

Iron, bronze, and the dead

The first systematic account came from the geologist and archaeologist Madeleine Colani, who reached the plateau under the École française d’Extrême-Orient in May 1931 and worked the fields across the following years, publishing her two-volume Mégalithes du Haut-Laos in 1935. Colani opened a cave near Site 1, noted holes in its roof that she read as a crematorium chimney, and proposed that the jars belonged to a mortuary system: bodies reduced — by fire or by exposure — and the cleaned remains gathered and interred. Around the jars, not inside them, she and later excavators recovered the furniture of the dead: human bone, ceramic vessels, stone and glass beads, spindle whorls, iron blades and tools, bronze ornaments, ceramic ear-discs, ground-stone objects, charcoal. Bone is rare within the vessels themselves — ash has turned up inside only a handful, at two sites, and may be far more recent than the jars.

The largest jar at Site 1, the most-visited of the fields surveyed by Madeleine Colani — via Wikimedia Commons (CC BY-SA 3.0)

This is the material signature of the Iron Age as it expressed itself across mainland Southeast Asia: communities working iron and casting bronze, trading beads and metal along routes that ran from the salt-rich valleys of the northwest toward the sea, organized enough to mine stone and raise monuments to their dead. Colani herself situated the plateau on such a network, threading from Assam in the northwest to the central Vietnamese coast in the southeast, with the jar fields commanding a corridor through the highlands.

The reading that has held — that the jars are vessels of secondary burial — fits the evidence without exhausting it. In a secondary-burial rite the corpse is first defleshed, by exposure, decomposition, or fire; later the bones are collected and given their final placement. The jar, on this account, is the station of transformation: the body is set within or beside it during the long interval of becoming bone, and the cleaned remains are then buried in the surrounding ground, beneath the discs, with their goods. The interpretation is the strongest available. It is not closed. No text from the jar-makers survives; the function is inferred from association, and the association, while consistent, is circumstantial.

How old, and how long

Dating the fields has been its own long labor. Inscription on the UNESCO World Heritage List in 2019, as the Megalithic Jar Sites in Xiengkhuang, fixed the conventional span at roughly 500 BCE to 500 CE, with possible extension toward 800 CE — an Iron Age window recognized under the criterion that honors exceptional testimony to a vanished people’s funerary tradition. That range, long the working consensus, has since been pulled open at both ends.

A 2021 study combining optically stimulated luminescence on the sediment trapped beneath the jars, uranium-lead dating of the stone, and radiocarbon on human remains and charcoal produced a two-layered chronology. The OSL signal — which records when buried grains last saw sunlight, and so dates the moment a jar was set down on the ground — placed the jars on the landscape startlingly early, as far back as roughly 1240 BCE and through to about 660 BCE. The radiocarbon dates on the burials clustered far later, in the ninth to thirteenth centuries CE. The jars, in other words, may have been raised in the second and early first millennium BCE, then used and reused as a hallowed ground of the dead for two thousand years and more. As the study’s lead, the researcher Louise Shewan of the University of Melbourne, put it together with Dougald O’Reilly of the Australian National University and the Lao Department of Heritage, the data show the sites maintained an enduring ritual significance from the first placement of the jars into historic times. The fields were not a single generation’s project; they were an inheritance, returned to across the whole arc of the region’s pre-modern history.

This makes the jars older than every state that later rose around them. By the time Funan drew Indian letters and gods into the Mekong delta in the early centuries CE, by the time Champa raised brick towers along the Vietnamese coast, by the time the Khmer Empire cut its great reservoirs and the Sukhothai kings declared their Tai realm to the southwest, the jar fields had stood for a thousand years or more. The jars are not the work of those kingdoms and owe them nothing; they belong to a highland mortuary world that predates the Indianized courts entirely and was already ancient when those courts arose. The plateau lies in modern Laos, but the vessels speak of no dynasty the chronicles name.

Giants and victory-wine

Against the long silence of the makers, the living tradition of the plateau supplies a story. The jars, the telling goes, are the work of a race of giants who once held this high country, and of their king, named in the accounts as Khun Cheung — Khun Jeuam in other renderings — who fought a long campaign and won it. To celebrate, he had the giants cut these enormous cups to brew and store a victory feast of rice wine, lau hai: lau, the drink, and hai, the jar. The greatest vessels were the cups of the greatest giants, the largest of all the king’s own. A variant holds that the jars were not carved at all but cast, molded from a paste of clay, sand, sugar, and animal hide hardened to the look of stone.

The legend is folklore, and it knows itself as such; it explains the inexplicable scale of the things and gives the dead king a monument the size of his appetite. The archaeology contradicts it on every testable point — the jars are quarried stone, not cast paste; they held bone, not wine. Yet the two accounts are not simply rivals. Both reach for the same thing the jars themselves insist on: that these were made by people of more than human capacity, for purposes weightier than the everyday, and that what was set inside them mattered enough to move mountains of rock. The giant-king’s victory cups and the secondary burial of the cleaned dead are two grammars for the same awe.

A mortuary horizon, and its neighbors

Sandstone jars grouped on a hilltop at Site 2, near Phonsavan — Adam63 (Adam Jones), via Wikimedia Commons (CC BY-SA 3.0)

The Lao jars do not stand wholly alone. Stone-vessel mortuary traditions of broadly the same kind recur across the wider region — sandstone jars in the Dima Hasao district of Assam and the Jaintia Hills of Meghalaya in northeast India, and the great stone vats called kalamba on the Bada plain of central Sulawesi in Indonesia. Across these widely separated highlands runs a common idea: that the bones of the dead belong in cut stone, set in the open landscape. The Lao fields are by far the largest and most numerous expression of it, but they are a regional dialect of a shared funerary language, not an isolated invention — and not, on the evidence, the direct ancestor or descendant of any of the others.

Set wider still, the jars take their place in the company of the world’s other stone-marked grounds of the dead, where a people without writing left their deepest convictions in worked rock. The cliff villages and burial niches of the Ancestral Puebloan Southwest, the oracular sanctuary at Delphi where the Greeks read a fissure in the rock as a mouth of the underworld — these are not relations of the Lao jars, and no thread of contact joins them. They are parallels in a human habit: the conviction that stone is the proper register for what outlasts the body. The architecture of such a belief — the soul or spirit understood as separable from the flesh and needing a station for its passage, the dead returned to as presence rather than absence, the long horizons of return that some traditions name reincarnation — is everywhere implicit in the jars and nowhere stated by them. The makers built the apparatus of a cosmology and left its doctrine unwritten.

Research and the wounded ground

The modern study of the fields runs from Colani’s 1935 survey to the Plain of Jars Archaeological Research Project, a partnership of the Australian National University, the University of Melbourne, and the Lao Department of Heritage, whose excavations have re-opened Site 1 and whose 2020 survey documented dozens of new fields. The decisive turn was the multi-method dating program whose radiocarbon, OSL, and zircon results split the chronology of placement from the chronology of use. Each advance sharpens the same residual puzzle: the burials can be dated, the stone can be sourced, the quarries mapped — and the people who first conceived of burying their dead in carved stone, in the second millennium before the common era, remain anonymous, their language unknown, their reasons reconstructed only from what they buried.

The ground itself carries a second, modern wound that conditions all of this. Between 1964 and 1973 the plateau lay under one of the most intensive aerial bombardments in history. The Xiangkhouang highlands were contested terrain in the Second Indochina War, and the campaign that began as Operation Barrel Roll in December 1964 made Laos, per head of population, the most heavily bombed country ever recorded — more than two million tons of ordnance, including hundreds of millions of cluster submunitions. A large fraction failed to detonate. Tens of millions of these “bombies” remain in the soil, and they still maim and kill. The consequence for the jars is direct: of the many fields, only Sites 1, 2, and 3 have been cleared sufficiently for visitors, who must keep to marked lanes between markers laid down by clearance teams such as the Mines Advisory Group, working the plateau since 1994. Survey and excavation move only behind the slow advance of deminers. The Iron Age field and the twentieth-century war are layered into the same earth, and to dig for the older dead one must first make the ground safe of the more recent dead-making.

The unfinished jars still lie at the quarries, scored from the bedrock and left. Somewhere between that block of stone and the cleaned bone laid in the ground beside the finished vessel lies the whole intent of the people who began this — an intent legible in every weight they moved and silent in every word they did not leave. Read together, the cleaned bones, the lidded vessels, and the stone discs that capped them point one way: these were mortuary jars, the apparatus of a secondary burial in which the dead were exposed and then gathered into the stone. The 2021 luminescence dates stretched that practice across nearly two millennia of the same fields opened, filled, and reopened — one rite kept on this plateau far longer than any empire that has yet risen and fallen around it.

→ Related: Iron Age · Soul · Spirit · Reincarnation · Funan · Champa · Khmer Empire · Sukhothai · Ancestral Puebloan · Delphi