Kin no Yu

Ranked among Japan's three oldest hot springs, Arima Onsen is a historic site beloved by the likes of Toyotomi Hideyoshi. Among its two spring types, the reddish-brown "Kinsen" and the clear "Ginsen", "Kinsen" can be enjoyed for drop-ins at Kin no Yu springs. This hot spring is a rich, iron and salt-laden sodium chloride strong saline spring (high-concentration neutral hot spring). Although the water is colorless when it first emerges, it oxidizes when exposed to air, turning a distinctive reddish-brown.

Inside, there are two baths: "Ichi no Yu" (Men’s bath), inspired by bamboo, a key element in Arima's traditional crafts, and "Ni no Yu" (Women’s bath), themed around Arima’s famous maple park, Zuihoji. Each bath features two tubs, one set at a hotter 44°C and the other at a milder 42°C, allowing guests to choose their preferred temperature.

Next to the facility, a free foot bath is available for those short on time. It’s a convenient way to experience the famous waters. As an extra bonus, visitors can purchase a combined ticket with Gin no Yu hot springs for just 1,200 yen, making it easy to enjoy both spring types.