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Soviet nuclear-powered icebreaker "Lenin" followed by icebreaker "Yermak" traversing the Northern Sea Route, 1961
(hexbear.net)
Fun fact: Icebreaker Lenin was the world's first nuclear-powered ship that launched in 1957, exactly 40 years after the revolution. In 40 years the Soviets managed to go from an agrarian feudal state to harvesting the atom for power and just a few years after this ship was launched, traversing the cosmos. :)
