When a farmer renovating a fish pond in Bac Ninh, northern Vietnam, uncovered two ancient boats in 2025, the discovery revealed more than an unusual surviving structure. Radiocarbon dating placed the remains in the second century AD, while seeds and fruit fragments recovered from 12 compartments are now helping researchers investigate ancient food supplies, river transport and trade between Vietnam’s lowlands and uplands.
The Discovery
The two boats were discovered accidentally in Cong Ha neighbourhood, in what was then Ha Man ward, Thuan Thanh town, now Song Lieu ward, Bac Ninh province. After their recovery, specialists collected samples and used radiocarbon, or carbon-14, dating to establish an estimated age of nearly 2,000 years.
The finds have since become the subject of continuing research. At the National Archaeological Report – 2026 conference in Hanoi, experts presented further observations about the boats’ construction and the plant remains found inside them.
Their interpretation is not yet settled. Shipbuilding specialist Do Thai Binh describes the structures as double-hulled vessels, with two hulls connected to support an upper platform. Archaeologist Dr Nguyen Viet, director of the Southeast Asian Prehistory Center, has questioned whether the remains represent a conventional boat at all, suggesting instead that they could be a floating structure.
This distinction matters. The structures may provide evidence of an unusual form of water transport, but their exact purpose and the nature of the upper construction remain unresolved.
Meanwhile, the plant remains offer a separate line of evidence. Researchers are examining whether the material represents transported goods, provisions or vegetation deposited naturally after the structures entered the wetland environment.
What Archaeologists Found
The two structures retain substantial portions of their original form. According to Do Thai Binh, their double-hulled design involved two connected hulls that acted like pontoons, providing buoyancy for a structure above them.
He also identified differences in the surviving structural components. A secondary crossbeam that would have linked the sides in the middle was missing, while a principal beam at one end had a major load-bearing role. Given the design's apparent limitations in rough water, Binh proposed that the structures were intended for river travel rather than open seas or exposed estuaries.
He suggested that the upper platform, estimated to cover more than 100 square metres, might have supported a pavilion or living space used by people of high status, such as nobles, royalty or tribal chiefs. He also proposed that movement could have been powered by oars and poles, with two stern rudders used to steer. These are expert interpretations, not confirmed reconstructions.
Nguyen Viet observed that the structures were tilted by approximately 10 degrees, with one side facing the shore and the other facing the river. This orientation may have contributed to differences in preservation between the two sides.
The botanical assemblage is another major component of the discovery. Researchers collected soil from the boats’ compartments and screened it for seeds, fruits and other plant material. Preliminary classification identified a wide range of specimens, including apricot and plum remains, star fruit, beans, large woody fruits and olive-related material.
One of the most numerous finds was sấu, a fruit used in northern Vietnamese cooking and in preserves. Researchers recorded 129 sấu seed or fruit specimens. They also identified 53 neem seed samples, 31 samples of Terminalia chebula, 30 apple seed samples and 11 acerola cherry samples.
Other remains included 13 chestnut fruit stalks and 28 kapok tree thorns. Gac fruit seeds, wild pineapple bark, frangipani seeds and seeds attributed to Ficus species were among the material reported as occurring in one boat but not the other.
These remains provide a detailed picture of the plant material preserved within the structures, although not every specimen necessarily arrived there as cargo.
Historical Background
The boats have been dated to the second century AD, during the late Dong Son period as described in the source report. Their discovery in northern Vietnam places them within a landscape where waterways could connect settlements and facilitate the movement of people, food and other products.
The plant assemblage may help researchers explore those connections. Chestnut trees are associated with upland and mountainous environments, while the report identifies tropical forest products, including wild pineapple and gac fruit, among the material under study.
The presence of these different plant types raises the possibility that goods moved between ecological zones. River transport could have offered a means of bringing products from inland or mountainous areas towards settlements in the Red River Delta.
However, the existence of a plant specimen alone does not prove that it was traded. Researchers must distinguish material deliberately carried aboard from seeds or other organic remains that entered the structures through natural processes.
The boats’ unusual construction also adds to the archaeological questions surrounding the site. If Binh’s interpretation is correct, they may represent a form of river-going vessel with a broad upper platform. If Nguyen Viet’s alternative is closer to the evidence, they may instead have served as a floating structure rather than a conventional boat. Further examination is needed before either interpretation can be treated as definitive.
Scientific Analysis
Two main lines of investigation are advancing understanding of the discovery: dating the wooden structures and classifying the plant remains.
Carbon-14 analysis placed the boats in the second century AD. This provides the principal chronological framework reported for the finds. The available account does not provide the exact laboratory results, sampled materials or calibrated date ranges, so a more precise chronology cannot be established from the reported information alone.
The botanical study involves collecting soil from individual compartments, screening it and identifying preserved seeds, fruits and other plant fragments. Researchers are examining their distribution across the two boats to assess whether the pattern is consistent with stored supplies or a natural deposit.
Plant remains were reported in 12 compartments, with material distributed relatively evenly from compartments one to six in both boats. The density increased towards the stern, where the greatest concentration of seed and fruit fragments was recorded.
This pattern led researchers to suggest that the middle and rear compartments may have been used to store food supplies. It is a plausible interpretation, but distribution alone does not establish exactly how the compartments were used.
The team has also classified the remains according to whether they were likely to represent transported products or natural deposits. Terminalia chebula, chestnut fruit stalks, Terminalia catappa and gac fruit were identified as transported goods. Rice-plant thorns, vines and unidentified pieces of wood were interpreted as natural deposits. Other remains, including sấu, Melia azedarach, local apples and acerola cherries, could have entered as cargo or through natural processes.
Why This Discovery Matters
The Bac Ninh boats bring together evidence about ancient construction, plant use and possible river-based exchange. Their survival in wet, oxygen-poor sediment has preserved organic material that would often decay in more exposed conditions.
According to Dr Nguyen Thi Mai Huong of the Institute of Archaeology, the wetland environment along the river helped limit biological degradation. Clay-rich sediment covered the structures, creating conditions that restricted exposure to air and oxygen-rich groundwater.
The botanical evidence is particularly valuable because it allows researchers to investigate the movement of plant products rather than relying solely on durable artefacts such as pottery or metal objects. If the transported-goods interpretation is supported by further analysis, the finds could help document connections between mountainous areas and the Red River Delta.
The contrast between probable cargo and natural deposits is central to that argument. Researchers have identified some specimens as likely trade goods, but other material remains ambiguous. The findings therefore point towards possible exchange networks without proving that every plant type was deliberately carried aboard.
What would provide the strongest evidence for ancient trade here: the types of plants recovered, their distribution within the compartments, or a clearer understanding of the boats’ original function? The answer will depend on how well the botanical findings can be connected to the structures and their archaeological context.
What’s Next?
The research team has continued studying the boats since their discovery, with further results presented at the 2026 national archaeology conference in Hanoi. The work described in the report includes detailed structural observations and the preliminary identification of botanical material.
Further analysis could refine the classification of the seeds and fruits, strengthen the distinction between cargo and natural deposits, and clarify how the material was distributed within the compartments.
The boats’ construction also requires continued assessment. Researchers will need to investigate the surviving structural elements and the proposed upper platform before establishing whether the remains represent double-hulled vessels, a specialised floating structure or another form of watercraft.
The source report does not specify a timetable for additional excavations or a final conservation and display plan. For now, the two structures remain important archaeological finds whose construction, function and contents are still being investigated.
Conclusion
The ancient boats discovered beneath a fish pond in Bac Ninh have yielded a rare combination of preserved structural remains and plant material. Radiocarbon dating places them in the second century AD, while the seeds, fruits and woody specimens provide clues to food storage and possible exchanges between different regions of northern Vietnam.
The precise function of the structures remains disputed, and researchers have not established that every botanical specimen was cargo. Nevertheless, the finds offer a valuable opportunity to study ancient river transport and the movement of plant products through the Red River Delta nearly two millennia ago.
FAQ
1. How old are the ancient boats found in Bac Ninh?
Carbon-14 dating places the structures in the second century AD, making them nearly 2,000 years old. The source describes them as belonging to the late Dong Son period.
2. What was discovered inside the boats?
Researchers identified a varied collection of seeds, fruit remains and other plant material across 12 compartments. Finds included 129 sấu seed or fruit specimens, chestnut fruit stalks, neem seeds and several other plant types.
3. Were the structures definitely boats?
No. Shipbuilding specialist Do Thai Binh interprets them as double-hulled boats, while archaeologist Nguyen Viet has suggested that they could be a floating structure rather than a conventional vessel.
4. Do the plant remains prove that ancient trade took place?
Not by themselves. Researchers consider several plant types likely transported goods, while others may represent natural deposits or could have entered the structures by either route.
