Osorezan (Mount Osore)

You smell it from the bus. Sulphur, then the sight of a caldera floor covered in bare grey and yellow rock with steam coming out of cracks in it, and beyond that a lake so acidic that almost nothing lives in it. Osorezan is one of the three great sacred mountains of Japan alongside Koya and Hiei, and unlike them it looks the part in the most literal way.

The temple is Bodaiji, founded by legend in 862 by the monk Ennin after a vision told him to find a mountain shaped like this one. The path through the grounds crosses ground called Sai no Kawara, the dry riverbed of Buddhist belief where dead children stack stones. Parents come and stack stones with them, and leave pinwheels, which turn constantly in the wind. There are thousands of them. It is a difficult place to walk through quickly.

Past that, the shore of Lake Usori is white sand and clear turquoise water and is called Gokuraku-hama, the beach of paradise, sitting directly beyond the hells. The contrast is the entire point of the layout.

Four wooden bathhouses stand on the grounds, fed by the hot springs, and entry to them is included in the 500 yen ticket. Bathing in strongly sulphurous water inside a temple that represents the border with the dead is a strange twenty minutes. Bring a towel. Silver jewellery will tarnish.

Itako, blind spirit mediums who speak for the dead, gather during the July festival. There are only a handful left and they are elderly, so this tradition is closing. The site is open from May to October and shut for the rest of the year under snow. Buses run from Mutsu in about forty minutes.