“Goshiki-numa” means “Five-Color Ponds,” a very appropriate name for these colorful, volcanic ponds near Mt. Bandai (磐梯山) in Bandai-Asahi National Park.
An eruption by Mt. Bandai in 1888 created landslides that blocked rivers to create numerous ponds and marshes north of the mountain. Volcanic soil, local flora, and waterweeds created these distinct and pretty colors in the water. Emerald green, cobalt blue, and even red. The larger ponds have colorful names like Aonuma (Blue Pond 青沼) and Akanuma (Red Pond 赤沼).
The left photo shows the largest pond named “Bishamon-numa” (毘沙門沼) where they had rental rowboats and even koi fish. Beautiful colors (both the pond and fish).
There’s a nice 3.6-km nature trail that goes along the major ponds for a leisurely 90 min. It’s a really pleasant walk and the pond colors are stunning. The right photo shows the Aonuma Blue Pond (5.7 meters deep). Just avoid going on rainy days due to slippery/muddy ground. 🚣🏻
Closest station is Inawashiro Station (Banetsusai Line) where buses go to Goshikinuma in 25 min. First walk to Bishamon-numa Pond, then stroll along the other ponds until the Ura-Bandai Kogen Eki bus stop (where buses go to the train station).
Official (Japanese): https://www.urabandai-inf.com/?page_id=141