Located in Shimosuwa Town, Suwa District, Nagano Prefecture, 'Tanga no Yu' is a historic communal bathhouse that originated from a lodging facility called 'Tanga-ryo,' built during the Kamakura period for traveling ascetic monks. Renovated and reopened in December 2012, it now features a new outdoor bath in addition to its traditional high-temperature baths. The water quality is sodium-calcium sulfate-chloride hot spring (low osmotic pressure, alkaline, high temperature) with a pH of 8.7. The source temperature is 56 degrees Celsius, with water emerging at 52 degrees at the spout. The clear, colorless water has a soft, gentle feel on the skin. It has long been known as a spring effective for healing cuts, and legend has it that warriors wounded in battle would bathe here. The indoor baths offer two temperatures: 'moderately hot' (approximately 45 degrees) and 'hot' (approximately 47 degrees), while the outdoor bath is set at a milder 42 degrees for leisurely soaking. Known for its exceptionally hot water among Shimosuwa Onsen bathhouses, it is particularly popular with hot spring enthusiasts. At 300 yen for adults, open year-round from 5:30 AM to 10:00 PM, it is conveniently located near Suwa Taisha Shimosha Harumiya shrine.