Here is an "interesting" review of the experience at one of these top-tier springs:
Considered one of the "Three Famous Springs" of Japan, the water here is alkaline and feels like a smooth lotion on the skin, earning it the nickname "Beauty Spring." 8. Hakone Onsen (Kanagawa)
: High concentrations of specific minerals (sulfur, iron, or carbon dioxide) recognized for health benefits. Notable Gensenfuro Destinations Destination Notable Feature Highest acidity in Japan Largest variety of spring types Ancient "Gold" and "Silver" springs Noboribetsu Famous for its "Hell Valley" scenery Rustic, forest-themed outdoor baths on the list or specific chemical properties of these waters?