7 Clues Revealing the Plain of Jars Secrets

Right in the middle of a highland plateau in central Laos, you’ll find over 2000 massive stone jars sitting in the grass, and to this day, nobody can say for sure who put them there.

We have no written records to look through, no confirmed name for the people who carved them, and not a single surviving settlement to study.

All we have are these jars lined up across plateaus and hilltops, almost like they’ve been waiting centuries for someone to finally explain what they are.

I’ve traveled there twice, once in 2001 and again in 2010, and more sites had opened up to the public between those two trips.

During that second visit, the guide walked us single-file along a dirt track while pointing out live cluster bombs sitting inches away in the grass. He also highlighted the small plastic landmines that seemed to sprout like mushrooms after being unearthed with each heavy downpour.

Just a few weeks ago apparently, a cow had chewed one – and had its fucking head blown-off.

This is the reality of the most bombed archaeological site on the planet, which makes the mystery even harder to solve.

giant jar plain of jars laos — Plain of Jars – Site 1: The largest vessel – known as Jeuam’s (Cheung’s) Victory Cup – stands 3 meters high and is associated with a Laotian legend of giants and a drinking party.

We’re left with two massive questions: who actually built this place, and what was the point of it all?

If you’re looking to solve the mystery of who these people were and why they left thousands of multi-ton stone vessels, you have to look at the clues they left behind.

Clue 1 — The Scale: Hand-Carved Chaos

To get a feel for this place, you have to realize it isn’t just one “plain.” We’re talking about 2,100 jars spread across 129 different locations. Some spots are lonely, with just a single jar watching a valley, while others— like Site 1 — are crowded with nearly 400 jars.

When you’re standing there with a cold BeerLao in hand, watching a cow wander between these megaliths, the scale hits you – standing from 1 to 3 meters tall and weighing up to 6 tons. And because every single one was hand-carved, no two look exactly the same.

Archaeologists have documented 31 distinct design styles. Some rims are flat, some are recessed, and some have prominent collars. To me, that suggests this wasn’t a weekend project. No, this was a civilization-wide obsession that likely lasted for dozens of generations.

The jars are carved mostly from sandstone and limestone, and if you head over to the quarry near Site 2, you can still see where they were hewn.

Clue 2 — The “Lids” That Weren’t Lids

For decades, everyone assumed the stone discs found lying around the jars were lids. It makes sense, right? A jar needs a top.

But when you look closer, the math doesn’t work.

None of these discs actually fit the jar openings, and they were never found sitting on top of the vessels. Instead, archaeologists found them lying face-down over burial pits in the dirt. Some are carved with human figures or circular patterns. These weren’t lids; they were grave markers. People were also being buried in the ground around the jars.

This tells us the jars were just one part of a much larger “city of the dead.”

Clue 3 — The Cremation Cave at Plain of Jars Site 1

Just a short walk from the main cluster of jars at Site 1 is a natural limestone cave that holds a dark secret.

There are two holes cut right through the ceiling to act as man-made chimneys.

cremation cave plain of jars in laos — Entrance to the “Cremation Cave” at Site 1 at the Plain of Jars.

A French archaeologist named Madeleine Colani surveyed this spot in the 1930s and found charcoal dating back nine thousand years. The theory? This was a prehistoric crematorium.

When I stood inside, I could still see the soot staining the upper walls — dark patches that a thousand rainy seasons haven’t been able to wash away. Today, local visitors leave small stone stacks on the cave floor as it still remains sacred.

It’s a quiet, heavy place that reminds you these jars weren’t for storage — they were for the transition between life and whatever comes next.

Clue 4 — The Site 75 Discovery (The “Distillation” Theory)

The biggest breakthrough in the jars mystery happened in 2016 at Site 75, about 70 kilometers northeast of Phonsavan.

Researchers found a massive jar — over 2 meters wide — that was packed with the remains of at least 37 different people.

This changed everything.

The bones weren’t just tossed in; they were placed there over several centuries. They were found alongside glass beads traced back to India and Mesopotamia, proving these “mysterious” people were players in global trade routes.

The current leading theory is that the smaller jars were used for “distillation.” A body would be placed inside to decompose, and then, once the process was done, the bones were moved into a large communal vessel like the one at Site 75.

It sounds macabre, but seemingly, it kept a community together even after death.

Clue 5 — The Logistics of Power

How do you move a 10-ton sandstone jar 8 kilometers across the most rugged highland terrain in Southeast Asia?

That’s the question that keeps archaeologists guessing.

Some jars were moved 100 kilometers from their quarries. But what’s even weirder is that no jar fragments have ever been found along the transport routes. Meaning: they didn’t drop or smash a single jar.

This clue tells us that whoever these people were, they had a well structured society. You don’t move 10-ton stones with a few friends; you do it with a massive, organized workforce, wooden sledges, rollers, and a lot of engineering.

Those imported beads and glass found in the graves tell the same story: that these people were wealthy enough to bury expensive foreign goods with their dead. And exactly how important a person was seems measured by the size of the jar.

The biggest jars were almost certainly for leaders, while the smaller jars and ground burials were placed around them – so when you look at the landscape, you’re seeing a social hierarchy carved into stone across the plateau.

plain of jars hill quarry in laos — Plain of Jars hill quarry site 2.

Clue 6 — Myths, the Frogman, and a Vanished Culture

Lao legend speaks of a giant king named Khun Cheung who defeated his enemies in a massive battle and ordered these enormous jars to brew rice wine for the victory party.

The story goes that the biggest jar was reserved for the king himself, and while that makes a great tale, it doesn’t explain anything from an archaeological perspective. But it’s good to know because over the centuries this legend was the only explanation locals had.

Yet looking at Site 1, there’s a specific jar with a carved figure known as the “frogman” — a human shape with arms raised and knees bent. This is a massive clue because it looks almost identical to rock paintings found in Guangxi, China, from the same period (500 BC to 200 AD). This suggests these people weren’t isolated, but rather part of a cultural web that stretched across borders we only drew on maps recently.

But then, around 500 AD, the people of the Laotian plains just … vanished. They left no written language, no houses, and no settlements.

We have their death relics, but we don’t have any insight into their lives.

Clue 7 — The Scars of the Secret War

You can’t talk about the Plain of Jars without talking about the “Secret War” episode of the Vietnam War.

Between 1964 and 1973, the US dropped 270 million cluster bombs on Laos. About 80 million of them didn’t go off.

War is one reason we don’t have many answers.

war debris uxo exposives and bombs at the plain of jars in laos — War debris on the Plain of Jars: LEFT: T-76 tank and guide Tanud, son of Sousath – the man who cleared mines and convinced the Laotian govt. to allow him to open the plain for tourists. Pointing to live cluster bomb (UXO). RIGHT: B-52 bomb crater near jars; more UXO on route to Raven Fire Base, ran by Hmong and Thai mercenaries because America wasn’t meant to be in Laos, hence “The Secret War.” Yet, the CIA had their Raven spotter planes there, and B-52s would arrive and bomb the hell out of the area, trying to counter communist insurgents.

Out of 129 sites, only 7 are open to the public.

The rest are still “guarded” by unexploded ordnance (UXO).

Many jars are shattered — not by time, but by direct hits from 2,500-pound bombs. The craters are still there, right next to the ancient stones.

It’s a jarring (pun intended) reminder that history isn’t just something that happened a long time ago; it’s something we’re still walking through.

These massive stone jars outlasted the people who carved them and survived a war that nearly-leveled the plateau, yet they still reveal new secrets with every excavation and hopefully more dots will be joined in the future (for example: are the Badu Valley megalithic statues and jars of Sulawesi related to the Plain of Jars and an empire spanning South East Asia many thousands of years ago?)

Planning Your Trip to the Plain of Jars

Getting There:

From Luang Prabang: A 6-7 hour minivan ride. It’s a “hairpin turn” kind of journey, so bring motion sickness tablets if you’re prone to it.

From Vientiane: You can take a bus (8-10 hours) or check if the Phonsavan Airport (XKH) has resumed flights (it has been under renovation recently).