Akanuma (Goshikinuma Pond Group)
Akanuma (Red Pond) is part of the Goshikinuma Pond Group, a colorful cluster of around 30 shallow ponds and swamps formed when Mt. Bandai erupted in 1888 and triggered a landslide that blocked a nearby river.
It is fed by spring waters originating in the acidic, iron-rich Copper Pond (also named Akanuma), a crater lake high on the northern slope of Mt. Bandai. The water, despite the pond's name, usually appears greenish with only slight red hues. The red comes from iron-rust residue that accumulates on the roots of the reeds and other aquatic plants growing in the pond.