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open-air bath; rotenburo; rotemburo
旅館の露天風呂で夜空を眺めた。
I gazed at the night sky from the inn's open-air bath.
その温泉宿には山を一望できる露天風呂がある。
That hot spring inn has an open-air bath with a panoramic mountain view.
冬の寒い日に露天風呂に入ると格別に気持ちいい。
Soaking in an open-air bath on a cold winter day feels especially good.