Originally published Sept. 22, 2015; updated Feb. 19, 2016

FRIGAARD CAVE, TRONDHEIM, Norway — Deep within a Norwegian hillside, thousands of US Marine Corps combat veterans await their next assignment. They are lined up in rigid rows. They are clean, fresh and ready. They are prepared to deploy worldwide.

"You can put a key in any of these vehicles and it'll turn on," declared Kevin Finch, a civilian working for the Corps.

He was guiding a group of visitors through a vast, built-for-the-purpose cave filled with military vehicles belonging to the US Marines.

"Many of these vehicles have been used hard, but they don't look like it," Finch said. "Fender benders and scratches are cleaned up, touchup paint applied." The vehicles, displaying a variety of paint and camouflage schemes, look show-floor new.

They await their next assignment while in the care of the Marine Corps Prepositioning Program-Norway: MCPP-N, or "McPippin" in milspeak.

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"These vehicles look new, but they've all been used," Finch explained during a visit Sept. 9 by Deputy Defense Secretary Robert Work. "The Norwegians do a fantastic job of putting them back together," Finch added.

The lion's share of the maintenance work here, Finch said, is done by the Norwegians. More than 70 Norwegian civilians, under military leadership, work on the vehicles and keep the cave facilities spotless.

"We rebuild or replace engines, transmissions," said Norwegian Army Capt. Ola Gilberg, cave manager of the Frigaard cave. "Not depot-level maintenance, but we perform preventative maintenance on all vehicles."

The caves are large — wide passageways and high ceilings, with a smooth concrete floor, and well-lit. Caves have a constant temperature and humidity, Finch pointed out. "There are no issues with corrosion."

The Frigaard cave, one of eight in the program, holds a variety of vehicles including armored amphibious vehicles, high mobility multipurpose wheeled vehicle variants, medium tactical vehicle replacements and logistics vehicle system replacements, snow-capable tracked vehicles, tank recovery vehicles, along with trailers and towed carriages.

Other caves hold armored vehicles, including M1A1 Abrams main battle tanks and light armored vehicles. Also stored are earth-moving equipment, generators, bulk fuel and bulk liquid systems, water production system, shelters, tents, netting and tool kits. Aircraft support equipment includes tow tractors, cranes, deicing equipment and arresting gear.

The eight caves are placed in various locations in the region surrounding Trondheim. Three caves hold ground equipment, three are configured for munitions and two hold aviation support equipment.

The caves were all built-for-the-purpose, not modified from existing formations, and were conceived under a Cold War plan to preposition Marine equipment in Europe for the defense of NATO. The first cave opened in 1982, the complex was completed in 1988. The caves are managed by the Marines' Blount Island Command, which oversees all Corps prepositioning programs.

But in 2012, the program began to reconfigure and modernize the facility to support a modern Marine Air Ground Task Force. "We're now at the tail-end of that effort," Finch said. "It'll be completed in 2016."

The modernization work also included, according to the Marines, placing gear and heavy rolling stock in the caves specifically to support armored vehicles.

The equipment in the caves, according to the Marines, can support an expeditionary brigade of roughly 15,000 US Marines, with enough supplies to operate for 30 days.

But gear routinely is broken out for operations and exercises. More than 6,000 items were withdrawn in 2003 for Operation Iraqi Freedom. By 2005, the caves were down to about 30 percent full, but have gradually built back up. Across the facility in September, about 70 percent of the storage capacity is being used. More gear, from multiple sources, is expected to arrive in Norway in coming months, driving capacity up to nearly 100 percent.

Exercises drive some withdrawals — a map in the complex depicting worldwide deployments showed vehicles used as far away as Cambodia. A major breakout will take place early next year, when the Norwegian-led Exercise Cold Response takes place. The exercise, held every two years, will involve about 2,000 US Marines and up to 16,000 military personnel altogether, and take place in February and March.

Cold Response is not a NATO-only exercise. In 2014, Belgium, Canada, Denmark, Estonia, Germany, France, Ireland, Lithuania, the Netherlands, Norway, Poland, Spain, Sweden, Switzerland, the United Kingdom and the US participated.

The US 2016 budget request includes $3.2 million to cover the exercise. According to US budget documents, participating Marine formations include a Marine expeditionary brigade/regiment staff, one infantry battalion, a tank company, one unit of Marine prepositioning ship enablers and a Marine logistics group.

Norwegian State Secretary for Defense Øystein Bø, who accompanied Work on the Sept. 9 visit to the Frigaard cave, noted that "this facility was built for our defense but now has expanded in use around the world. It's important to Norway to show our commitment."

Work was impressed by what he saw.

"This is an excellent location," he told a group of Norwegian reporters. "The equipment in these caves go all over the world, as far as Cambodia. This facility has a very wide reach."

He said there were no plans to expand the caves, but praised the work of the Norwegians.