Ohino Hakkai (meaning eight oceans in Japanese) is made of eight spring water ponds located in Oshino village, Yamanashi prefecture, and registered as UNESCO world heritage site in 2013.
The spring water comes from melting snow on the slopes of Mt.Fuji. When Mt.Fuji erupted around 800 AD, the flow of lava sprit it into Lake Yamanaka-ko and Lake Oshino-ko. Lake Oshino-ko was dried up into a basin due to river erosion, then only eight springing ponds were left.
The water went deep underground Mt.Fuji and was filtered through porous layers of lava for over 20 years, resulting in very clear spring water. The water of Oshino Hakkai is called “the spring of God” in English because Mt.Fuji is believed to be sacred mountain.