Kin no Yu

Kin-no-yu ("Gold Water") is the larger of the two municipal public bathhouses in Arima Onsen, one of Japan's oldest and most storied hot-spring towns near Kobe. It sits at the center of the old spa town and is the classic place to soak in Arima's famous kinsen ("gold spring") water.

The gold (kinsen) water

The kinsen is a sodium-chloride, iron-rich spring. On contact with air the dissolved iron oxidizes, turning the water a cloudy reddish-brown "gold" color. It is also high in salt and metasilicic acid.

• The salt forms a protective film on the skin that retains warmth and moisture, so bathers stay warm long after leaving the bath.
• Traditionally valued for skin ailments, muscle and joint pain, poor circulation and sensitivity to cold.
• Arima's source waters emerge very hot; the bathhouse offers two indoor gold-water baths of differing temperatures for each gender.

Heritage

Ranked among Japan's oldest hot springs (alongside Dogo and Shirahama), Arima Onsen was cherished for centuries, including by the warlord Toyotomi Hideyoshi. The present facility descends from Edo-period baths and was rebuilt with a Western-influenced design; it carries an inscription honoring it as an early holy hot spring.