Marunuma Dam

Marunuma Dam is a buttress dam in Katashina featuring a grid-patterned wall supported by distinctive pillars rising 32.1 meters high. The structure spans 88.2 meters across the waterway and was engineered with careful attention to load distribution and stability.

Construction began in 1928 under Nagaho Mononobe's leadership as part of Japan's early infrastructure development. This period marked a turning point in the nation's approach to water management and technical progress.

The site holds status as an Important Cultural Property, reflecting Japan's industrial advancement through engineering excellence. Walking around it, you can sense how the structure represents the nation's pride in technical innovation from that era.

The dam is viewable from outside, though interior access to upper levels typically requires special permission. The best visiting time is during clear weather when you can clearly see the structural details and surrounding landscape.

Among the eight buttress dams built during the Taisho and early Showa periods in Japan, this structure is the largest of the six that still remain. This rarity makes it a valuable example of early power generation engineering that has survived to the present day.

Location: Katashina

Inception: 1928

Height: 32.1 m

Length: 88.2 m

Website: https://tepco.co.jp/rp/business/hydroelectric_power/mechanism/dam/list/marunuma.html

GPS coordinates: 36.82389,139.33972

Latest update: December 8, 2025 20:01