Hiruzen: Gateway to Daisen-Oki
Gently sloping uplands and the famed peaks of the Daisen-Hiruzen Highlands welcome visitors to Daisen-Oki National Park: 69,410 hectares of diverse scenery spread across Shimane, Okayama, and Tottori Prefectures. Originally established as Daisen National Park in 1936, the park was renamed after being expanded to include parts of Shimane and the Hiruzen Highlands in 1963. The Hiruzen area encompasses a wealth of ecosystems spanning mountain forests, clear rivers, and broad grasslands. Two endemic plant species and numerous endangered plants and animals make their homes here, relying on the park’s protected status to preserve their fragile populations. People in this area have adapted to the environment over the centuries, developing a flourishing culture that is inseparable from the landscape.
The Hiruzen Highlands and the “Three Peaks of Hiruzen” (known collectively as the Hiruzen Sanza) are part of the Chūgoku Mountain Range, which stretches from eastern Yamaguchi Prefecture to western Hyōgo Prefecture. Like the neighboring Daisen range, the Hiruzen mountains were shaped by repeated volcanic eruptions as lava and volcanic debris hardened into domes that formed the various peaks. At lower elevations, the mountainsides are blanketed with natural woodlands of oak and chestnut, interspersed with plantations of Japanese cedar and hinoki cypress. Higher up the slopes, Japanese beech, oak, and other deciduous broadleaf trees shelter rare montane plant species. Throughout the area, broad swathes of grassland are maintained by annual controlled burns. This age-old practice preserves the grassland habitats of resident endangered species and also ensures a consistent supply of the plants used in traditional handicrafts.
Today, the Hiruzen Highlands is a popular vacation and resort area with outdoor activities such as hiking, camping, and cycling. The elevation of 500 to 600 meters above sea level generally ensures cooler temperatures even in the hottest months, making the region an ideal summer destination. The cool climate and black volcanic soil support several agricultural specialties, including blueberries, an unusual species of wine grape, and daikon radishes prized for their uniform shape. Hiruzen is also known for its rolling pastures, Jersey cows, and high-quality milk.
Rich natural resources provide the raw materials for many local industries. These include unique traditional handicrafts such as Gōbara lacquerware, a style that uses only local materials—both the wooden vessel bases and the sap that is processed into lacquer come from trees grown in Hiruzen. The final product is polished with locally mined diatomaceous earth, a layer of silica-rich sediment formed from the fossils of tiny phytoplankton called diatoms. A long-running lumber industry has evolved to include modern technologies like cross-laminated timber (CLT), which is made by gluing sawn lumber boards in perpendicular layers to form large panels. These eco-friendly panels make more efficient use of forestry resources while providing increased structural stability, heat resistance, and versatility compared with standard lumber.
The beautiful and varied landscapes of the Hiruzen Highlands are deeply interwoven with local culture. Historically, the mountains isolated the villages of Hiruzen from coastal areas, but also helped preserve intangible cultural assets. A local dance called the Ōmiya Odori, for example, is thought to have its roots in court dances from more than a thousand years ago. It is still performed as part of the summer festival.