Nagato Onsen Yasuragi no Yu, located next to a roadside station in Nagawa Town, Nagano Prefecture, is a day-use hot spring where you can enjoy a sodium sulfate spring known as boshōsen, which is gentle and moisturizing for the skin. The facility features a dry sauna of around 100°C and a cold plunge bath whose temperature varies seasonally between about 11 and 24°C, plus a spacious outdoor area for pleasant open-air cooling.