Ito Onsen Shizuoka Izu
- Location
- Ito, Shizuoka, Izu Peninsula, Japan
- Water type
- sodium chloride
- Temperature
- 45 °C
- pH
- 7.3
Water profile
Relaxing — deep, immediate muscle release.
Loaded with major ions — the essential minerals (Ca, Mg).
Dense, salty water — you float without effort.
Ito Onsen in Ito city, Shizuoka prefecture, is one of the Izu Peninsula's most historic coastal hot spring resorts, where chloride-rich sodium waters have been used therapeutically since the 8th century and where the Dutch trading ship De Liefde's pilot Will Adams — the real-world inspiration for James Clavell's novel 'Shōgun' — supervised the construction of Japan's first Western-style ocean-going vessel in 1604, cementing Ito's role in Japan's complex relationship with foreign maritime culture. The coastal onsen town faces Sagami Bay, with Mount Fuji often visible across the water on clear mornings, while the abundant trawler-fresh fish of Ito's port supports a seafood restaurant culture of extraordinary quality. The Izu Geopark's extraordinary concentration of volcanic hot springs, lava caves, and submarine geology makes Ito an anchor point for exploring Japan's most geothermally active peninsula.