More than 2,000 British military personnel deployed to Norway in mid-March for one of the UK's largest exercises of the year.
Royal Marines, Royal Navy ships and an air group from Joint Helicopter Command took part in Exercise Cold Response, before it was cut short due to the coronavirus outbreak.
The training, which was held inside the Arctic Circle where temperatures can drop to as low as -30°C, aimed to enhance the UK's cold weather capability.
Major Chris Armstrong, from 45 Commando, told Forces News: "We are going through an important transformative process within the Royal Marines at the moment.
"So, this exercise is demonstrating some of the capabilities that we have at the moment and [some] that we wish to procure in the future.
"[We are] really trying to push the boundaries of commandos raids and going back to our roots of putting small bands of determined men ashore to have an overwhelming effect on our enemy."
As well as surviving the cold, Royal Marines from 3 Commando Brigade - the Royal Navy's elite fighting force - had to practise being ready to defend Norway, in addition to sharpening their amphibious assault skills and more.
Norway relies heavily on the support of its NATO allies.
The country shares a 122-mile border with Russia, and Moscow is placing greater emphasis on the Arctic region as rising sea temperatures make it increasingly accessible.
The area is rich in natural resources and earlier this year, Russia set out a 15-year Arctic strategy plan.
Moscow said it wanted to encourage cooperation in the region, but over the past decade, the country has reopened several Arctic military bases, as well as announcing plans to expand its icebreaker fleet.
Lieutenant General Rune Jakobsen, Commander of Norwegian Joint Headquarters, said although they do not see Russia as a threat, he does feel that they need to be prepared.
"What we see in their daily life is that they behave mostly professionally," Lt Gen Jakobsen said.
"But we have seen some indications where they have acted aggressively doing simulated air attacks on Norwegian cities, on Norwegian infrastructure.
"The future is uncertain, but they are no threat today."
Watch: The Commando Logistic Regiment kept vehicles moving during Cold Response.
"Russia's active and that's one of the reasons we have the NATO alliance," Major General Matt Holmes, Commandant General of the Royal Marines, told Forces News.
"By training regularly with our partners, inter-operable and closely integrated we are active and ready for whatever may be required."
This year marks the first of a 10-year training programme between the Royal Marines and their Norwegian counterparts.
Other nations also took part in Exercise Cold Response, including the Netherlands, France and the US.