Hakone Kowakien Yunessun.

Yunessun is less of a traditional onsen and more of a sprawling hot spring theme park, uniquely catering to those who prefer swimwear over nudity. The facility is split into two distinct zones. The main Yunessun area is a playful, family-friendly complex where visitors soak in vats of real red wine, aromatic coffee, sake, and green tea. It features waterslides, cave baths, and an expansive "Aegean Sea" pool, making it a rare inclusive option for tattooed travelers. For those seeking a quieter experience, the Mori no Yu area offers a conventional, clothing-free alternative with serene open-air baths overlooking the Hakone mountains. With its digital wristband payment system and diverse dining options, it functions as a comprehensive day-trip destination that prioritizes novelty and relaxation in equal measure.