Kusatsu onsen, one of the most popular onsen destinations in Japan, has about 3 million visitors per year and is located a few hours from Tokyo in Gunma prefecture. Kusatsu is well known for its onsens, yubatake, shirane-san (shirane crater lake) yugama and yumomi (hot spring curing).

Yubatake, meaning “hot water field”, is probably the best known part of Kusatsu and is the main source of hot spring water. When the water hits the surface it is a seering 65 degrees before it is cooled down by Yubatake’s wooden conduits before it is distributed to the various ryokans and public baths.One of the main attractions at Kusatsu is the picturesque, emerald green Shirane san, a crate lake at 2160 meters above sea level. Shirane san last erupted on February 21, 1983 and has a diameter of 300m, a depth of 30m and a temperature of 18 degrees.

It is unclear as to where the name ‘Kusatsu’ came from but there are several explanations. The explanations include:
1) that buddhist monks named it. In sacred writings ‘Daihannyagyou’ – buddhist scriptures it was written that there were famous hot springs in the south.
2) it originated from the Ainu people. In shiga-kogen there is a hot spring called Hoppo onsen.
For example, in Shigakogen there is a hot spring called Hoppo Onsen. The “Hoppo” part of the name means “hot spring” in Ainu.
3) Kusai Izumi (means smelly spring), so people called it Kusai Izumi, so the name Kusatsu could have originated from this.
4) The word ‘kusatsu tsumi’, which was used as a memory keyword for a traditional Japanese tanka (poem) which referred to illness? The word could have originated from this.
5) Kusatsu was originally called ‘Kusadu’, but this eventually changed to Kusatsu. Perhaps consonants were not pronounced clearly over the years.

One of the most famouns onsens in the area is called ‘Nishinogawara onsen’, the largest onsen in Kusatsu at 500 square meters. Antoher well known onsen is Otaki no yu, known as the ‘onsen department’ because of the large variety of onsens. They also have a pool (based on a German pool, called TerumeTerume).

There is a well known ‘Ashi-yu, Yukemrite’ (foot onsen) where you can bathe your tired feet for free.