A wall of jagged spires and broad cliffs rises vertiginously above the hulking grey glacier. The icy valley floor is ridged like a washboard and pockmarked with greenish ponds of melted snow.
From a two-seater Lama helicopter, you can see a few pockets of green wheat and apricot orchards in the lower stretches which dazzle like hallucinations, before the enormous wall of rock and ice rears up suddenly – the barrier between Pakistani Baltistan and India's Ladakh. China lies north, beyond the farthest crest. This is the world's highest battlefield. In the shadow of K2, on the stony ridges and immense icefields of the contested Siachen glacier, nuclear-armed foes India and Pakistan are locked in a dance of death. But another enemy stalks both sides in the frigid wastes: the cold that has killed more soldiers than bullets.
Combat gear for Major Karim, fighting for Pakistan's 40th Battalion of the Siachen Brigade, includes delicate white kid gloves to prevent his finger from freezing to the trigger.
The Pakistanis and Indians on the plains are seared by summer temperatures nudging 50 degrees. But the warriors on the snowbound battlefields at the northernmost extremity of the disputed Kashmir province are clad in down parkas and white balaclavas. All troops on Siachen must wear at least three sets of gloves – kidskin, wool, then fleece-lined polyester. Summer temperatures can drop suddenly to minus 20C.
Marching roped together to prevent anyone from vanishing down a hidden crevasse, soldiers and officers are continually pushed to the limits of their physical capabilities. After every 15 steps, they halt for two minutes to catch their breath.
Since a ceasefire was agreed on 26 November 2003, Major Karim has not had to actually fire on any of the thousands of Indian troops hunkered down on the glacier. But in spite of this formal truce, the neighbours are continuing the world's most expensive and most futile conflict, slugging it out for 21 years over a 250-square-mile wedge of unforgiving mountain terrain.
This is terrain that would challenge expert mountaineers, only there are no Sherpas catering for these climbers. A total of about 10,000 troops are stationed around Siachen, and India, at exorbitant expense, outmans Pakistan. Keeping the military supplied costs these developing nations the equivalent of more than £1m a day.
Truce or not, the mountains echo with terrifying sounds that unnerve the men.
"In our sleeping bags, ears to the ground, we hear the groan of the glaciers. Avalanches sound like mortars. The crack of a new crevasse sounds just like artillery fire. We have nightmares of being swallowed in our sleep by the ice," says Major Karim.
The men are at constant risk from avalanches or rock slides if they manage to ward off hypothermia. Compared to the perils of rock and ice and the relentless cold at heights between 15,000 and 20,000 feet, where on windy winter days temperatures can plummet to minus 70C, the enemy is a comparatively minor irritation. Even at the height of the hostilities, combat wounds from bullets or rockets were responsible for only 20 per cent of deaths on the ice.
Now officers take pains to acclimatise their platoons, who tackle the mountain in gradual stages. Raw Pakistani troops arrive at Gyari Battalion HQ at around 13,000ft. They spend at least a week at base camp, learning how to cope with cold and heights and, while trekking up the snout of the nearest glacier or playing cricket on the world's highest pitch, become attuned to the symptoms of body failure before they are allowed to march further uphill.
Moving to extreme altitudes can cause brain or lung damage from acute mountain sickness and kill a man within 24 hours. Men drown in the frothy pink foam spewed by collapsed lungs. Insomniac soldiers routinely suffer headaches and hallucinations, and the slightest lapse, such as a dropped glove, can result in frostbite. After only brief exposure of the naked eye, snowblindness is common. Even the packmules must wear snow goggles above 16,000ft.
In capricious weather, soldiers cannot rely on helicopters and must evacuate their fallen comrades by sledge. Military patrols leave long after sundown, when the snow firms up under ice and there is less risk of slides. Midnight manoeuvres are the norm.
To perfect the "lizard crawl", one fighter tethered by ropes slithers down a rockface head first, firing at targets below while completely exposed. The cover of darkness is crucial against snipers.
From the air, the panorama is exhilarating: a high desert of sand dunes gives way to broad rivers heavy with silt, like liquid asphalt. Some 27 mountain peaks here tower above 23,000ft – 13 of them have never been climbed.
The place is bleak and immense – with scant resemblance to the busy concrete relief map, flagged with hand-lettered name tags, where Major Waqas points out strategic passes and 135 enemy outposts scattered across scale-model glaciers.
Chutes of snowmelt hurtle down past the helicopter from the peaks for hundreds of metres and evaporate to mist before hitting the bottom.
On a ridge stands a cluster of scuffed glassfibre igloos, originally designed to house South Pole scientists. Half a dozen men, smudged with kerosene pitch, emerge to wave at the chopper. They keep frozen goats and chicken carcasses dangling from a ledge, like a restaurant deepfreeze.
"Only Pakistani, Indian, and Nepali pilots can land at such altitudes, above 6,000 metres," boasts Major Jawad. "But after we lost nine helicopters to accidents, we have orders to use the running drop. To cut the motor in such thin air is risky."
One at a time, passengers are harnessed and lowered by cable, often whipped close to the tail rotor by ferocious winds. The dangling soldiers are unhooked as soon as their feet touch the snow. In winter, the snowdrifts can be neck deep.
Following the harshest winter this century, half a dozen Pakistani sepoys were stranded for 11 months inside a glassfibre igloo on a forward outpost, facing off against the Indian troops who control the improbable heights. Deep snow and black ice precluded any chance of rescue, because even the nimble Lama helicopters could not operate in such brutal conditions. Whenever the blizzards abated, ice fog would obliterate the horizon.
The soldiers eventually returned late this spring, weakened and numbed; normally, men are granted leave after three months' duty.
Despite nine rounds of peace talks over 20 years, the pace of diplomatic negotiations to solve this bitter border war between India and Pakistan at Siachen is moving at glacial speed. Following 58 years of animosity, including three wars, bilateral discussions are very guarded, although twice the two countries came very close to calling off the conflict which is so redolent of colonial-era Great Gamesmanship. In June, there was tantalising talk that Siachen could soon be transformed into a demilitarised zone. Visions of a bi-national scientific research centre for extreme climate conditions or an adventure training centre for elite mountaineers have been mooted.
Calls for reconciliation, after a flurry of border crossing by poets, rock bands, dance troupes, cricket teams, Kashmiri separatists and ordinary bus passengers, sound on both sides of the border.
A fortnight ago, India's Prime Minister, Manmohan Singh, visited his frontline Siachen troops, huddled in their prefabricated igloos at 6,300m. The 72-year-old leader announced: "The time has come that we make efforts that this battlefield is converted into a peace mountain."
There was an immediate caveat, however. To preserve prestige and security, there would be "no redrawing of boundaries". Next, the Indian Army's chief, General JJ Singh, brandished a "roadmap" for Indian troop withdrawal.
Sayeed Ali Shah Geelani, Pakistan's foreign office spokesman, said: "We have been wanting troop withdrawal for some time ... but things are not moving forward. Horns are locked."
After so much blood spilt on the ice – a combined 5,000 deaths among the subcontinent's most elite fighting units – neither side wants to be the first to withdraw from what they call their "frozen frontier".
Both sides concede that Siachen – which translates as "wild rose" in the Balti language – is the most logical place to declare a demilitarised zone. If this plan were to succeed, it would become a litmus test for any lasting solution to the Kashmir dispute, which began to bedevil the two neighbours just two months after the British raj was partitioned into Muslim Pakistan and Hindu India.
Pakistan's General Pervez Musharraf and India's Prime Minister Singh met recently in Delhi and agreed that their new peace process was " irreversible". General Musharraf insists that Pakistan is anxious to "grasp the moment", now that the nuclear neighbours are led by men who trust one another. Although General Musharraf grabbed power in 1999, shortly after ordering the seizure of a 17,000ft ridge overlooking Indian-held Kargil and shelling a critical supply road, he says he is eager to settle the conflict over Kashmir – "the earlier the better".
The CIA has warned for 12 years that this dispute is the likeliest nuclear flashpoint on earth.
"It is silly to be fighting over this territory," Dr Rifaat Hussain, a military historian in Islamabad, declared. "It is a monument to folly."Reuse content