Nagano Iida City
A sky-high onsen with panoramic Shinshu views and “the skin lotion bath”
Tenku no Shiro Sangitei Honkan is a Japanese-style onsen inn in Iida, Nagano Prefecture. It sits on a gentle hill where Iida Castle once stood, looking out over the city spread below and the grand panorama of the Southern Alps stretching into the distance. Its pride is a silky, alkaline natural onsen known as “the skin lotion bath,” and you can take in the spectacular views from an open-air bath that seems to float in the sky or from the spacious main bathhouse. There is also a mist sauna where a fog carrying the onsen’s minerals gently envelops you, along with a private semi-open-air bath for time to yourself. Together with a beautiful Japanese garden that changes with the seasons, the inn promises a special stay where the mind can unwind.

A panoramic main bathhouse overlooking the city of Iida below and the majestic ridges of the Southern Alps in the distance. Its wonderfully open sky-high open-air bath makes you feel as if you are floating in the air, letting you take in the clear air and rich nature of southern Shinshu with your whole body. The silky, alkaline natural onsen, praised as “the skin lotion bath,” wraps smoothly around your skin.

A semi-open-air private family bath where you can enjoy the renowned waters without reserve in a secluded space away from the bustle. With someone special or alone in the quiet, you can have the silky onsen water, prized for its skin-beautifying qualities, all to yourself for as long as you like. At your own indulgent pace, it offers a special bathing experience that brings deep peace to body and mind.

A mist sauna where fine, fog-like steam rich in the onsen’s minerals gently wraps around your whole body. The soft heat warms you to the core without feeling stifling and brings on a natural sweat. It moisturizes the skin while encouraging circulation, so along with deep relaxation, a pleasant warmth lingers long after you leave the bath.
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[Day-use bathing] 12:00–21:45
Bathing is permitted if tattoos are covered with stickers or similar, or if you use Nanten, the private bath available by reservation only.
By car
Parking for overnight guests: 60 spaces (first come, first served). Motorcycles and bicycles are directed to covered parking.
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