Yuri Kozyrev / NOOR for TIME A paratrooper from the 173rd Airborne Brigade looks out over the perimeter of Forward Operating Base Shank in Afghanistan's Logar province on Jan. 22, 2013

For the past few years, American troops in Afghanistan have used the winter months to make progress in counterinsurgency before the next fighting season. But with the end in sight for the U.S. military presence in Afghanistan, American forces have a different kind of mission this winter. This is the first in a series of stories by Nate Rawlings, assigned to document the dismantling of the U.S. installations in Afghanistan in the walk-up to the withdrawal of troops by the end of 2014.

You can be forgiven, upon landing in Kabul, for initially forgetting you’ve entered a war zone. Leaving the city’s slightly shoddy airport, I descended into its frenetically congested streets and saw thousands of people go about their daily lives, seemingly unaware that the rest of the world always attaches the word war next to their country.

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But quickly, reality sets in. Within a few miles of the airport, you see the blast walls, those towering slabs of concrete that surround the government agencies and upscale hotels. In just the past few months, Kabul suffered a suicide bombing that killed 12 people and an hours-long gun battle at the Spozhmai Hotel, a resort not far from Kabul. The New Year hadn’t started much better. There had been a bombing barely a week before I arrived.

On the morning of Jan. 21, two days after I flew into the city, a loud boom and rattling windows shook me from my sleep about 10 minutes before my alarm went off. Insurgents had attacked the headquarters of the city’s traffic police, detonating a suicide bomb and a car bomb, before taking refuge in the police building. After a nine-hour operation, Afghan security forces finally rooted out the last of the militants; three policemen and five insurgents were dead.

Despite the ongoing chaos at the traffic police headquarters, business in Kabul continued as usual. The drive north from the city to Bagram Airfield took the usual estimated time: one hour. Once a staging ground for the 1979 Soviet invasion of Afghanistan, Bagram is now one of the three largest NATO bases in the country and the main hub for all operations in the north and the east of Afghanistan. In the coming months, Bagram will play an even larger role in the American withdrawal, becoming one of the main centers for retrograde, the military term for returning to the U.S. all the vehicles, weapons and equipment that have accumulated in Afghanistan during 11 years of war.

According to a recent report to Congress by the Government Accountability Office, the U.S. military has an estimated 90,000 20-ft.-long containers of equipment scattered throughout Afghanistan. All together, this equipment is worth more than $36 billion, and it will cost more than $5.5 billion to return it to the U.S. or simply transfer for the use of Afghan government forces.

But the expense of retrograde is perhaps the least of the military’s worries. With a firm date set for nearly all American troops to leave Afghanistan by the end of 2014, the clock is ticking to inventory, consolidate and move that equipment. Nowhere is that more difficult than in Regional Command-East, which comprises most of the northeast of the country, including the mountainous areas along the border with Pakistan, an area that has seen some of the heaviest fighting throughout the war. Bagram is the largest base in Regional Command-East and is its logistical and transport hub.

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For the past several years, American troops have operated out of dozens of large and medium-size forward operating bases and dozens more combat outposts scattered throughout the mountainous areas along the Pakistan border. Bagram Airfield is the final stop for much of that equipment before it is flown out of the country, but to see where this process begins, one must navigate through the byzantine airlift system, hopscotching out to smaller and smaller bases.

The first leg on my journey to the American outposts came aboard a 30-seat Dash-8 prop plane, operated by a company called AAR Airlift. Long before the sun could burn through the morning haze and raise the temperature anywhere near freezing, I joined 11 soldiers and contractors who climbed aboard the white, slightly weathered airplane. The crew — a pilot, co-pilot and crew chief — wore a uniform of matching tan pants, combat boots and black fleeces. It was a far cry from a flight I took two years ago in Kandahar province in an ancient Sikorsky helicopter, where the bearded, hulking crew chief, dressed in insulated overalls and a T-shirt, asked passengers to come up one at a time for fear that the stairs — held by two rickety cables — might collapse.

On this plane flight from Bagram to Forward Operating Base Shank, the crew chief gave a preflight speech that was one part combat briefing one part standard preflight talk. After explaining what to do in case of ground fire and the location of a medical kit if we were shot down, he finished by saying, “Please ensure that all personal items are stowed and that your seat backs and tray tables are in the full upright and locked position.” And with that, we took off into the frigid fog.

After a 20-minute flight south over the snowcapped mountains, we landed at Forward Operating Base Shank, the third largest base in Afghanistan by square mileage. Shank is one of the major collection points for equipment headed to Bagram, a process already under way, as row after row of giant metal containers flank the base’s dusty roads. The retrograde operation at Shank is a kind of laboratory for what works and what doesn’t, as the troops of the 173rd Airborne Brigade try to clear out as much equipment as they can in the last few weeks before they rotate home. Their efforts may prove to be a battle plan for other units as they try to balance their core mission — assisting the Afghan forces — with retrograde: battling Afghanistan’s terrain, weather and attacks by a resilient insurgency to take everything home. It is now less than two years before the final troops will leave Afghanistan. The clock is ticking on a mission that is a logistician’s nightmare, one that will require precise execution, a little bit of improvisation and drastic changes in mind-set if it has any hope of succeeding.

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