Tōsan

region, Japan

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July 20, 2026

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Tōsan is a subregion within Japan's Chūbu region, located in central Honshu. It encompasses the prefectures of Yamanashi, Nagano, and Gifu. Historically, Tōsan was a significant center for sericulture, or silkworm raising, before World War II.

The region is characterized by its mountainous terrain and deep gorges, which are sources of hydroelectric power and popular tourist destinations. While rice is a staple crop, fruits and mulberry trees are also cultivated. Key industries in Tōsan include the manufacturing of precision instruments. The area's geography, with its high mountains, contributes to its distinct character within Japan.1

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Chūbu
Tōsan—consisting of the inland prefectures of Yamanashi, Nagano, and Gifu—was the sericultural (silkworm-raising) centre of Japan before World War II. In addition to rice, fruit and mulberry trees are grown; the major manufactures are precision instruments. The area’s high mountains and deep gorges are a…
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Tōsan—consisting of the inland prefectures of Yamanashi, Nagano, and Gifu—was the sericultural (silkworm-raising) centre of Japan before World War II. In addition to rice, fruit and mulberry trees are grown; the major manufactures are precision instruments. The area’s high mountains and deep gorges are a…
Read More