Oshino Hakkai

Oshino Hakkai, or the Eight Seas of Oshino, are a set of eight ponds located in the Fuji Five Lakes area, on the site of a former sixth lake that dried out several centuries ago. The eight ponds are fed by snowmelt from the slopes of Mount Fuji that filters down the mountain through porous layers of volcanic rock over a period of several decades. This makes the mineral-rich pond waters remarkably clear and pristine. Oshino Hakkai are part of the Mt. Fuji UNESCO World Cultural Heritage site, designated in 2013.

The ponds were originally known as the Fujisan Nemoto Hakko Sacred Grounds, or the Moto-Hakko. Eight is a significant number in Buddhism, and making a circuit of the eight ponds was a major part of Mt. Fuji worship. Religious groups would purify themselves in the ponds prior to climbing Mt. Fuji. However, Fuji worship declined after 1868, when the new government led by Emperor Meiji took measures to reduce the immense wealth and power of Buddhist sects, and religious ablutions at the ponds gradually ceased.

Many modern-day visitors to Oshino Hakkai seek out the ponds year-round for their views of Mt. Fuji, but winter offers a particularly stunning vista of the iconic mountain. That vista is the striking “Diamond Fuji” phenomenon, which can only be seen from certain places due to the position of the Earth. Diamond Fuji is when the rising or setting sun aligns perfectly with the peak of Mt. Fuji, as though the caldera is cupping the sun.

A small open-air museum, the Hannoki Bayashi Shiryokan, surrounds the largest pond. A small admission fee is required. The water in the Waku Pond is especially clear and clean, and visitors are encouraged to drink it and even take some home in a bottle.