Uploaded January 2021 | Updated September 2026, 2 hours ago

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We haven't got around to exploring every inch of land on our planet by foot yet, let alone what lies beneath the world's oceans and seas! There might be anything hiding down there, including countless undiscovered lifeforms. When we do go looking beneath the waves, we do sometimes find new life, but we also find surprising leftover relics and artifacts of human life - as you're about to find out by watching this video!