Ключевые слова: acidic nature, bathing, efficacy, fumarole, geothermal, gushing, gushing volume, hachimantai, hell, hell valley, hokutoseki, hot spring, hot spring bath, hot spring bathhouse, hot spring flowers, hot spring water, hot water, hydrochloric acid, japan, japans best, large spout, natural hot spring, onsen, onsen therapy, radium hot spring, rock bath, rocky surface, sightseeing spot, source, spa, spring quality, steam, stimulation, strong acid, sulfur, tamagawa, tamagawa onsen, thermal therapy, virgin forest, volcanic gas, volcano, yunokawa,