Why in news?
Japanese researchers announced the recovery of a remarkably preserved ceramic vessel from the bottom of Lake Biwa in November 2025. The pot, dated to roughly 10,000 years ago, offers new insights into the early Jōmon period and highlights the potential of underwater archaeology.
Background on Lake Biwa
Lake Biwa, located in Shiga Prefecture on the island of Honshū, is Japan’s largest freshwater lake. Shaped like the biwa (a traditional Japanese lute), it stretches about 64 km north to south and covers an area of 672 km². The lake occupies a tectonic depression and is considered one of the world’s oldest lakes, estimated to be more than four million years old. Its sole outlet is the Yodo River, which carries water southward to Osaka Bay. Biwa is a vital reservoir for cities such as Kyoto and Ōtsu, supports fisheries and pearl culture, and is celebrated for its scenic beauty and cultural importance.
The archaeological discovery
- Underwater ruins: The pot was found near the Tsuzuraozaki underwater site at a depth of about 64 m. This area is believed to have been a lakeshore settlement during the early Jōmon period, before rising water levels submerged it.
- Age and style: At roughly 10,000 years old, the vessel belongs to one of the earliest phases of Japanese pottery. It is about 25 cm tall with a pointed base and corresponds to the Jōmon Konan or Jinguji ceramic styles.
- Technology used: Researchers used an autonomous underwater vehicle equipped with high‑resolution three‑dimensional sonar to map the lakebed and locate artifacts. The pot’s excellent preservation is attributed to the cold, low‑oxygen environment and the protective layer of silt.
- Significance: Early Jōmon pottery provides clues about hunter‑gatherer societies transitioning to sedentary lifestyles. Discoveries from Lake Biwa help reconstruct ancient settlement patterns, ceramic technology and subsistence strategies.
Lake Biwa’s ecological and cultural value
Beyond archaeology, Lake Biwa is ecologically rich. It hosts endemic fish species such as Biwa trout and serves as a breeding ground for many migratory birds. Its waters feed irrigation canals and supply drinking water for millions. The lake’s shores have inspired poetry and art for centuries; the “Eight Views of Omi” were famous scenic spots celebrated since the Edo period. Environmental challenges such as eutrophication and invasive species have prompted conservation measures to protect this ancient lake.
Conclusion
The discovery of a 10,000‑year‑old pot under Lake Biwa demonstrates how technological advances in underwater robotics can illuminate ancient human history. As researchers continue to explore submerged sites, new artefacts may emerge that enrich our understanding of early Japanese civilisation. At the same time, preserving Lake Biwa’s ecological integrity remains critical for the well‑being of the communities and biodiversity that depend on it.
Source: IDR
