This is an open-air bath with no roof, separated into sections for men and women. The stones used in the bath are black and red "Asama stones," formed from the eruption of Mount Asama.

The bath features a gourd-shaped tub, which is considered a symbol of good luck in Japan. The tub’s arched edges provide a comfortable fit for your back and neck while bathing. The building is designed in the style of Kamakura architecture, inspired by the legendary tales of Minamoto no Yoritomo that have been passed down through the ages at Shibu Onsen.

This Western-style bathhouse was completed in 1950 and features stained glass and a bathtub modeled after Roman fountains. The hot spring water, which has been flowing since the Edo period, contains a high concentration of iron, causing the water to appear cloudy. It was once known as "Muddy Bath" due to this characteristic.

The largest of the private baths is in the shape of a ship, and was completely renovated in 2018 to become a bath with tile paintings called “Saigetsu-no-yu". It is an experience as if you have stepped into an ukiyoe woodblock print.

This circular bath is made of high-quality wood from Kiso, including sawara cypress.

The ingredients of the onsen have made it much whiter, but the red and black stones are cut out of the lava of Mt. Asama. Therefore, although it is a stone bath, it is not slippery and pleasant to the touch.

It is the same Asama stone as the onsen of Keiwa-no-yu, but the edge of the bathtub is made of wood. There is a relatively large space.

It is an onsen in a rock cave that was dug on the slope of a mountain shortly after the war. The caves from wall to ceiling are all piled with natural rock. It is also a popular private bath, but the source of the bath is partly different here. Occasionally, the texture of the hot water may change significantly. It is a phenomenon that occurs when there is a lot of third boring. Hot water is mixing 1st, 2nd and 3rd boring.