About 90 Marines from the 24th Marine Expeditionary Unit from Camp Lejeune carried out a mock air assault in Iceland in October 2018 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 Oct. 25, 2018, 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.

The 90 US Marines aboard the USS Iwo Jima were first loaded onto MV-22 Ospreys and CH-53 Sea Stallions.

Marines load onto a CH-53E Sea Stallion aboard USS Iwo Jima (LHD 7) while conducting an air assault in Icelandic terrain on Oct. 17, 2018.

(Photo by US Marine Corps)

Source: US Marine Corps

Then they were transported to Keflavik Air Base in Iceland.

A V-22 Osprey departs from USS Iwo Jima for an air assault in Icelandic terrain on Oct. 17, 2018.

(Photo by US Marine Corps)

Where they set up a security post.

A US Marine posts security at Keflavik Air Base in Iceland on Oct. 17, 2018.

(Photo by US Marine Corps)

Source: US Marine Corps

"During the air assault we landed on an airfield and immediately set up security which allowed for the aircraft to leave safely," Cpl. Mitchell Edds said.

US Marines post security at Keflavik Air Base in Iceland on Oct. 17, 2018.

(Photo by US Marine Corps)

Source: US Marine Corps

"We then conducted a movement to a compound where Marines set up security to allow U.S and Icelandic coordination,” Edds said.

A US Marine aims his weapon while posting security during a mock air assault in Iceland.

(Photo by US Marine Corps)

Source: US Marine Corps

After seizing the compound, the Marines hiked inland to a training site.

US Marines hike to a cold-weather training site in Iceland on Oct. 19, 2018.

(Photo by US Marine Corps)

"The climate Iceland offers allows us to test our gear in colder weather rather than just the heat," Cpl. Riley Woods said.

A Marine adjusts a fellow Marine's gear as they prepare to move for a cold-weather training hike in Iceland on Oct. 19, 2018.

(Photo by US Marine Corps)

In fact, they appear to have tried out their new cold-weather boots, which were just issued by the Corps.

Cold-weather insulated boots used by US Marines in Iceland on Oct. 19, 2018.

(Photo by US Marine Corps)

Source: US Marines

After what looked like a lengthy hike, the Marines finally reached the cold-weather training site.

US Marines overlook a training area from a hill in Iceland on Oct. 19, 2018.

(Photo by US Marine Corps)

Where they began setting up camp.

US Marines set up camp during cold-weather training in Iceland in October 2018.

(Photo by US Marine Corps)

Source: US Marine Corps

"We're just getting the gear out — the tents, stoves and stuff like that, making sure we know how to use it ... and making sure we know how to use it before we get to Norway," one US Marine said.

US Marines set up tents in Iceland in October 2018.

(Photo by US Marine Corps)

Business Insider contacted the US Marine Corps to find out more about the cold-weather training they conducted, but the Corps did not immediately respond.

Source: US Marine Corps

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