A Western-style bathhouse on the shore of Lake Suwa, built in 1928 by the Katakura silk dynasty for the welfare of local residents and now an Important Cultural Property. Its famous Sennin-buro is a marble pool 1.1 m deep — you bathe standing, pebbles underfoot, surrounded by stained glass and sculpture — named for the hundred people it can hold at once. It uses Kamisuwa's spring water and also has a sauna and jet bath. Adults ¥750, open 10:00–20:00 (last entry 19:30), closed 2nd and 4th Tuesdays. The 2nd-floor rest room (until 19:00) and canteen (11:00–15:00) are open to bathers, and tours of the hall building are offered. Eight minutes on foot from Kami-Suwa Station, handy for Suwa Taisha shrine and Takashima Castle.

✔ Verified operating: 2026-09 KURA／まめまる 2026-06（大人750円・10–20時 受付19:30・第2・4火曜休）

Prices and hours change. Check official sources before visiting.

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