Ichi-no-yu is a natural hot-spring sento on Shinkotoni's main street in Kita-ku, charging ¥500. Both sides have a high-temperature sauna; the men's side adds a 75–80 °C medium sauna with a jar of source water to pour over yourself outside, and the women's a 40 °C zeolite low-temperature sauna. The cold bath is 1.2 m deep, the open-air baths include a hinoki tub of spring water, and tattoos are refused. Open daily 10:00–24:00, cash only.