Manza Onsen

What to know

Perched 1,800 meters above sea level on the slopes of Mount Shirane in northwestern Gunma Prefecture, Manza Onsen (万座温泉) is a hot spring resort town renowned for its highly acidic, sulfur-rich waters. Sourced from Mount Shirane, these waters are among the most sulfuric in Japan and are believed to boost metabolism and improve blood circulation.

Manza Onsen features numerous hotels and ryokan with exceptional hot spring baths. The open-air baths are particularly delightful, offering excellent water quality and a serene atmosphere. With guaranteed snowfall in winter, it's one of the best spots near Tokyo for enjoying an outdoor bath in the snow. Below is a list of recommended ryokan and hotels that welcome both overnight guests and day visitors:

Ratings: best of the best best of Japan outstanding

Above the town, a small network of pleasant walking trails winds through the valley, passing many hot spring sources. Here you'll find Manza's Yubatake ("hot water field"), a pool where thermal waters collect—though it's too hot for bathing. One trail leads to an observation point with views over the town. Due to snow, these trails are closed in winter.

From mid-December to late March or early April, Manza Onsen offers skiing and snowboarding. The small resort has four lifts and is operated by the Manza Prince Hotel, which sits next to the slopes and provides rental equipment and package deals combining accommodation with ski passes.

Take the Hokuriku Shinkansen from Tokyo to Karuizawa (65 minutes, around 6,000 yen), then a Seibu bus from Karuizawa Station to Manza Onsen (110 minutes, 2,950 yen one way). Note there are only 2–3 buses daily, and JR passes are not valid on the Karuizawa–Manza Onsen buses.