A Strategic Location Between Two Rivers
Where the Chikuma River Meets the Yomase River
Yanagisawa Archaeological Site stretches along the eastern bank of the Chikuma River, just north of its confluence with the Yomase River, which flows from the Shiga Highlands. The settlement was built on a broad river terrace, covering an area approximately 800 meters from north to south and 600 meters from east to west.
The Chikuma River is one of Japan’s major rivers and has served as an important route for the movement of people and goods since ancient times. Around Yanagisawa, the river is relatively deep, and researchers have suggested that the area may also have functioned as a landing place for boats.
This strategic geographical position is thought to have contributed significantly to the development of the settlement. The site offers an intriguing glimpse into how waterways connected communities and facilitated the movement of people, goods, technologies, and ideas in ancient Japan.
The Excavations and Their Remarkable Discovery
Archaeological Research from 2006 to 2008
Excavations were conducted by the Nagano Prefectural Archaeological Center between 2006 and 2008, ahead of a river embankment improvement project undertaken by the Ministry of Land, Infrastructure, Transport and Tourism.
The investigations revealed evidence of settlements dating from the Jomon period through the Heian period. Among the most significant discoveries was a pit containing bronze objects dating to the middle Yayoi period.
The First Such Discovery in Eastern Japan
At first, archaeologists identified seven bronze halberds and one bronze bell. Further investigation revealed that the objects had been deliberately buried together in a single pit.
Until then, this type of combined burial of bronze bells and bronze halberds had primarily been known from western Japan. The Yanagisawa discovery was the first confirmed example in eastern Japan, making it an important archaeological breakthrough.
Daily Life in the Yayoi Settlement
Homes, Rice Cultivation, and Waterways
Excavations in the embankment construction area revealed the structure of a settlement dating from the middle to late Yayoi period. Archaeologists identified six pit dwellings, providing evidence of residential life in the community.
The remains of rice paddies and irrigation channels were also discovered, confirming that rice cultivation was practiced at Yanagisawa. Some of the ditches functioned as irrigation channels, while others appear to have marked boundaries between residential and agricultural areas.
These discoveries provide concrete evidence of how agricultural communities lived along the Chikuma River and contribute to our understanding of the development of Yayoi farming culture in the region.
Bronze Objects and the World of Yayoi Rituals
Bronze Bells and Bronze Halberds
The most distinctive feature of Yanagisawa is its bronze-object burial pit. The site produced five bronze bells and 13 bronze halberds, the largest quantity of such bronze objects discovered in eastern Japan.
These objects are believed to have been more than weapons or decorative items. Archaeologists consider them ritual treasures used in religious ceremonies and symbolic practices.
Evidence of Long-Distance Cultural Exchange
The bronze bells and bronze halberds are thought to have originated from production centers in northern Kyushu and the Kinki region of western Japan. Their presence at Yanagisawa demonstrates that the community was connected to a much wider network of cultural exchange.
The discovery is particularly significant because Yanagisawa was located inland, far from Japan’s western cultural centers. Not only bronze objects but also the rituals, customs, and ideas associated with them appear to have reached this community.
This evidence encouraged archaeologists to reconsider the traditional image of Yayoi culture as a phenomenon concentrated mainly in western Japan and to recognize the complexity of cultural exchange across the Japanese archipelago.
The Kuribayashi Cultural Sphere
A Center of Northern Nagano’s Yayoi Culture
Yanagisawa is located within the cultural sphere associated with Kuribayashi-style pottery. The Kuribayashi culture developed distinctive pottery styles and burial customs that differed from those of the Ina and Kiso valleys.
Its cultural influence is thought to have extended from the Hokuriku region to the Kanto region. Yanagisawa is located approximately 4 kilometers downstream from the Kuribayashi Archaeological Site, making it an important location for understanding how this culture developed and spread along the Chikuma River.
The modern Hokuriku Shinkansen also passes through this broader cultural region, symbolically highlighting the continuing importance of transportation routes that have connected communities across northern Nagano for centuries.
Climate, Environment, and Cultural Continuity
A Relatively Mild Environment Along the Chikuma River
The Yanagisawa Archaeological Site lies at an elevation of approximately 318 meters and benefits from a relatively mild climate compared with many other parts of Nagano Prefecture.
During the late Jomon period, some areas around the southwestern foothills of Mount Yatsugatake experienced a decline in population. In contrast, the number of archaeological sites in northern Shinano declined more gradually.
This difference suggests that communities along the Chikuma River may have maintained connections between Jomon and Yayoi populations. The distinctive Jomon-like elements found in Kuribayashi-style pottery provide an example of this possible cultural continuity.
National Important Cultural Properties
212 Artifacts from the Yanagisawa Site
The artifacts excavated from Yanagisawa include bronze bells, bronze halberds, pottery, stone tools, beads, and other archaeological materials. A total of 212 artifacts were designated National Important Cultural Properties in recognition of their historical and archaeological value.
The collection is preserved and displayed at the Nakano City Museum, where visitors can see the actual objects and learn more about the communities that lived in the Chikuma River region more than two thousand years ago.
A Glimpse into Ancient Beliefs
Among the discoveries are objects that offer clues about the spiritual world of the Yayoi people. One particularly intriguing example is a piece of pottery decorated with an incised image of a deer.
Such artifacts provide valuable clues for imagining the beliefs, rituals, and view of the natural world held by the people who lived here.
Visiting the Yanagisawa Archaeological Site Today
Today, riverbank improvement work around the Yanagisawa area has been completed, and explanatory signs have been installed at the archaeological site. Although many of the original artifacts are preserved elsewhere, visitors can explore the location and understand the geographical setting in which the ancient settlement developed.
For a deeper experience, a visit to the Nakano City Museum is highly recommended. Seeing the excavated artifacts alongside information about the settlement makes it easier to understand the significance of the discoveries and the connections between northern Nagano and other parts of ancient Japan.
An Archaeological Site That Offers a New Perspective on Ancient Japan
The Yanagisawa Archaeological Site is far more than a local archaeological site. Its bronze bells and bronze halberds provide important evidence of the spread and diversity of Yayoi culture across the Japanese archipelago.
Built beside the Chikuma River and surrounded by the mountains of northern Shinano, the settlement was a place where agriculture, transportation, cultural exchange, and religious traditions came together. The discoveries at Yanagisawa reveal that communities in inland eastern Japan were connected to distant regions and participated in a much broader cultural network than previously understood.
When exploring northern Nagano, visiting Yanagisawa together with the Nakano City Museum offers a fascinating opportunity to look beyond the region’s temples, hot springs, and mountain scenery and discover the deep layers of history hidden beneath the landscape.