Nanairo Dam

Nanairo Dam is a concrete gravity structure spanning the Kitayama River in the Kumano and Kitayama region, holding back a large reservoir. The facility was designed to harness water flow for hydroelectric power generation serving the surrounding area.

The Electric Power Development Company commissioned Obayashi Corporation to build this structure between 1963 and 1965. The project was part of Japan's broader effort to expand hydroelectric power capacity during the country's period of rapid economic growth.

The name translates to "seven colors" in Japanese, referring to how the surrounding mountains shift through different shades across the seasons. Visitors often notice these color changes most vividly during autumn and spring months when the landscape transforms.

The dam offers viewing areas where you can see the structure and the reservoir landscape clearly. Since the location is mountainous and somewhat remote, it is helpful to plan your visit and check access routes in advance.

The structure uses a straightforward gravity design to hold back water, a remarkably elegant engineering solution for this mountain region. This construction method allows the dam to remain stable and functional without requiring complex mechanical systems.

Location: Kumano

Location: Kitayama

Height: 61 m

GPS coordinates: 33.96028,136.00250

Latest update: December 9, 2025 18:42