Hokkaido Sobetsu Town
An infinity hot spring that blends with Lake Toya and an authentic sauna with breathtaking views
"The Lake Suite Ko no Sumika" is a luxury resort hotel in Sobetsu, Hokkaido. On the top floor, there is an infinity-style open-air bath that feels united with Lake Toya, offering the blissful sensation of bathing as if floating in the sky. From the sauna room as well, you can take in sweeping views of timeless nature, and the cold plunge bath using lake water provides a refreshing cooldown. Every room is equipped with a hot spring open-air bath, allowing guests to enjoy high-quality chloride spring water to their heart's content in a private space free from outside interruption.

The large bath on the top floor features an infinity-style open-air bath with the tubs spread out in three terraced tiers. Because of its structure extending toward the lake, you can enjoy an overwhelming sense of openness, as if you are floating in the sky while connected to Lake Toya. The water is a heat-retaining sodium-calcium chloride, bicarbonate, sulfate hot spring, known for its gentle feel on the skin. On clear nights, a sky full of stars spreads overhead, promising the ultimate bathing experience that unites you with nature.

Each room's terrace is equipped with a private hot spring open-air bath. The biggest appeal is that you can enjoy natural hot spring water as much as you like, whenever you like, without worrying about anyone's eyes. Seizing exclusive access to the beautiful lake view below, the time spent surrendering yourself to the water while feeling the pleasant breeze creates a special private experience that helps you forget the hustle and bustle of everyday life.

A scenic dry sauna with a panoramic view of Lake Toya. Through the large windows, you can gaze out at timeless nature and spend an exceptional moment available nowhere else in a quiet, calming space. The powerful heat wraps your entire body and draws out a deep sweat from the core. Right in front of the sauna room, water for hydration is also provided, supporting a comfortable sauna experience.

Just beside the sauna, there is a luxurious cold plunge bath with a pleasant texture, using lake water. The crisp, cool water refreshingly tightens your heated body and provides outstanding cooldown. In addition, there is also a jacuzzi-style cold plunge bath with bubbles rising from the bottom, gently relaxing your whole body with a massaging effect. You can smoothly transition to an outdoor air bath on the post-bath living terrace and sink into a deep sense of relaxation.
Availability and rates are shown on each booking site.
This page contains affiliate links. Booking through them costs you nothing extra.
Irregular Holidays
Hokkaido
Noboribetsu's welcoming hall, where the Oni Sauna and three renowned springs melt away body and mind
Hokkaido
A city-center hotel for making the most of Asahikawa. Relax with the warmth of birch and an authentic sauna
Hokkaido
An exquisite nature resort where you can immerse yourself in Shiretoko’s vast wilderness with stunning views of the Sea of Okhotsk and a sauna overlooking drifting ice in winter
JAPAN'S FINEST ONSEN & SAUNA
The Finest Onsen & Sauna in Japan
61 SELECTIONS
Most of what we surveyed never even made it onto this site. This book is a further cut from what did. Our editor bathed in every onsen and sauna in it, and wrote only what they confirmed on the ground.