Water held back by this large dam at the end of the Horomankyo Gorge is sent to Power Station No. 3 downstream of Horoman-gawa Inari Shrine (Geosite A6) via underground water pipes. Built in 1954, the dam has the highest water storage capacity (15,379,000 m3) of any privately owned facility of its kind in Japan. Two hydroelectric power plants in the Horomankyo Gorge generate approximately 10,000 kW of electricity for supply to local users.
The gorge ends here at the northeastern edge of the Horoman peridotite complex. Different landforms featuring metamorphic rock (e.g., amphibolite), plutonic rock (e.g., gabbro and tonalite) and other types extend from here to upstream areas in the north.
The forest road continues along the edge of the Apoi Mountains to Samani Town center (not described here).
