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exploration; expedition
子どもの頃、裏山の探険が一番の楽しみだった。
As a child, exploring the mountain behind our house was my greatest joy.
未知の洞窟を探険するために専門家が派遣された。
Specialists were dispatched to explore the uncharted cave.
北極の探険に挑んだ冒険家の記録を読んだ。
I read the account of an adventurer who attempted an expedition to the Arctic.