Arktika-class icebreaker
The "Arktika" class is a Russian (former Soviet) class of nuclear-powered icebreakers. Formerly known as "Project 10520 nuclear-powered icebreaker", they were the largest and most powerful icebreakers until the 2016 launch of the ship named Arktika. Ships of the "Arktika" class are owned by the federal government, but were operated by the Murmansk Shipping Company (MSCO) until 2008, when they were transferred to the fully government-owned operator Atomflot. Of the ten civilian nuclear-powered vessels built by Russia (and the Soviet Union), six have been of this type. They are used for escorting merchant ships in the Arctic Ocean north of Siberia as well as for scientific and recreational expeditions to the Arctic.
SS Manhattan (1962)
SS "Manhattan" was an oil tanker constructed at the Fore River Shipyard in Quincy, Massachusetts that became the first commercial ship to cross the Northwest Passage in 1969. Having been built as an ordinary tanker in 1962, she was refitted for this voyage with an icebreaker bow in 1968–69. Registered in the United States at the time, she was the largest US merchant vessel as well as the biggest icebreaker in history.