US Marine Corps
U.S. Marine with 24th Marine Expeditionary Unit posts security at Keflavik Air Base, Iceland, Oct. 17, 2018, during Exercise Trident Juncture 18.
About 90 Marines from the 24th Marine Expeditionary Unit from Camp Lejeune carried out a mock air assault in Iceland last week as part of the initial phase of NATO's largest war games since the end of the Cold War.
The NATO war games, called Trident Juncture 2018, will begin on Thursday in Norway and include more than 50,000 troops from 31 countries.
According to NATO, the purpose of Trident Juncture is "to ensure that NATO forces are trained, able to operate together, and ready to respond to any threat from any direction."
But the war games are also largely seen, by the East and West, as de facto training for a fight with Russia.
Along with the carrier USS Harry S. Truman, the US has sent about 14,000 troops to the games, and the initial mock air assault was to help prepare Marines for a large-scale amphibious assault to be carried later in Norway.
But that's not all the Marines did.
Here's how they trained in Iceland for a potential cold-weather fight with Russia.