In which country was the first nuclear icebreaker built?

"Lenin" is an atomic icebreaker, the world's first surface ship with a nuclear power plant.

The icebreaker was launched in 1957 in the USSR and entered operation in 1959, before being officially decommissioned in 1989. The icebreaker was intended to demonstrate the power of Soviet shipbuilding. Between 1960 and 1965 the ship travelled 85,000 miles, 65,000 miles of those through ice, clearing routes for soviet cargo ships. The ship had a couple of nuclear accidents, eventually rendering it irreparable. It is now a museum piece in Murmansk.