Yase, 672. The story goes: in a war over the throne, Prince Ōama is hit by an arrow. The villagers build a mound of earth, heat it, and heal his back. So the village was written "arrow-back".

The steam oven, the kamaburo: a dome of earth about two metres high. Inside, they burn green pine, rake out the ash and lay straw mats wet with salt water. When the steam has chased out the smoke, you crawl in and lie down.

The historians say no. The name means "many rapids", written that way since the 900s. The arrow is a legend. But the village did serve emperors: its men carried Emperor Meiji's coffin in 1912, and one man who served in Tokyo remembered heating the emperor's bath among his duties.

The oven is still open: 55 to 60 degrees. You take in a ceramic pillow and lie still. In Finland, we lie still too. We just never thought of the pillow.

Would you crawl in?

Sources: Kotobank, 竈風呂 (Heibonsha): an earth mound about 2 m high, green pine burned inside, the ash raked out, salt-moistened straw mats, bathers lie inside once steam has driven out the smoke. Heihachi Chaya, the operator (2026): 55 to 60 °C, a ceramic pillow, the arrow-wound legend. Japanese Wikipedia: かま風呂; 八瀬童子 (the 672 legend; Yase men bore Emperor Meiji's coffin, 1912; a man who served in Tokyo recalled heating the emperor's bath); 八瀬 (historians reject the legend; 八瀬, "many rapids", written so since the Engi era, 901 to 923).
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