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deep in the mountains; mountain recesses
祖父は山奥に住んでいる。
My grandfather lives deep in the mountains.
山奥には珍しい植物がたくさんある。
There are many rare plants deep in the mountains.
山奥の静かな温泉宿で家族と穏やかな時間を過ごした。
I spent peaceful time with family at a quiet hot spring inn deep in the mountains.