A chilly wind howled through the Bumla pass, the snow-bound border between India and China, one of the few recognised frontiers between the two gigantic Asian neighbours.
Situated at a height of 15,200 feet above sea level, the pass sits on the top of a craggily formed Himalayan range that separates the Tibetan plateau from the Indian sub-continent.
The huts which mark India's border post are but a few minutes walk to Chinese positions manned by People's Liberation Army soldiers in snow fatigues.
A handful of visitors, including this correspondent, are allowed to walk up to the barrier which marks the border crossing.
However, none are allowed to cross from either side, nor are goods allowed to be traded, even though trade between the two nations is expected to touch $100 billion in the current fiscal.
Tall peaks overlook the high pass as does an observation post built by the Chinese, which the Indian Army believes doubles up as a listening station.
Just 43 km away to the north of the Bumla pass is Tsona Dzong, in Tibet Autonomous Region's Shannan prefecture.
The Chinese have built a high-quality motorable road S202 from Shannan right up to Bumla.
Lieutenant General Utpal Bhattacharyya (Retd.), former director general of engineers and an expert on the India-China border, told PTI, "The Chinese have been trying a game of salami-slicing with us -- incursions in Ladakh, fortified villages near the Line of Actual Control in Arunachal Pradesh, and new roads right up to the border."
No villages have yet been built on the LAC in the Tawang sector, though there are reports of some having been built elsewhere on the border in Arunachal Pradesh.
However, two heavily fortified PLA camps are situated near Bumla with advanced landing grounds, and one of those is, what Indian defence experts believe, a missile site.
A western spur of the S202 leads to Namka Chu, where one of the first battles in the 1962 border war between the two nations took place.
This area has two more major PLA camps overlooking Indian positions on the Thagla ridge, where there were recent incursions by Chinese troops.
Earlier this year, the Chinese completed another major road through the Tsangpo river valley connecting Nyingchi city with Medog, the shortest route to the Arunachal Pradesh border to the east of Bumla.
A second railway route after the one which links Lhasa with China proper is expected to link Nyingchi with Sichuan soon.
"However, despite all these infrastructure projects, the PLA's engagement with us will remain a logistical challenge as they will still have to move men, material and food stocks from outside Tibet, as the barren plateau there cannot supply or support large armies," Lt. Gen. Bhattacharyya said.
Most defence analysts believe that though the situation on the border may appear tense, it is not necessarily a threatening one.
Major General Alok Deb (Retd.), former deputy director general of the Institute for Defence Studies and Analysis, told PTI, "With ongoing talks and attempts to disengage, there is no casus belli (cause for war) as of yet, but we have red lines which if crossed, will invite retaliation. It is logical to presume the same for the Chinese."
However, two years back, incursions in Ladakh had ended in an ugly clash where soldiers did lose lives, a fact which forced policy discourse in New Delhi to place China as the pre-eminent security threat ahead of Pakistan.
The road to Bumla passing through Tawang is a bumpy, back-breaking drive through snow and mud with mountains, aflame with rhododendron flowers, dropping down onto pristine lake shores.
The road uphill is dotted with army camps made of corrugated steel sheets and wood, ammunition dumps, artillery parks, stone bunkers and memorials to soldiers who fell in the India-China border war of 1962.
There are no villages on this drive as the air here is too thin even for local Monpa tribals. Nobody except soldiers, road maintenance personnel of the Border Roads Organisation and a few nomadic herders camp this high.
Reasons Lt. Gen. Bhattacharyya, "Chinese infrastructure is better than ours because Tibet is a plateau and the gradient is more conducive to construction there. Here, we have precipitous mountains plunging downstream."
The last time a flashpoint occurred on this border was in 1986 when the Chinese entered the high valley of Sumdorong Chu, to the west of Bumla, near Bhutan. This valley, where Indian troops used to camp in summer, was frequented only by yak herders. In winter it usually laid under deep snow and no one bothered to cross its virgin snows.
A company of PLA occupied Wangdung, a pasture to the south of Sumdrong Chu, which the Chinese claimed to be Sangduoluo He, and to the north of their version of the border.
While India accepts a borderline called the McMahon line agreed upon by the British and Tibet's then government in 1914 to be the border, China disputes it, especially in Arunachal Pradesh, most of which it terms as 'South Tibet'. The disagreement makes the border between the two neighbours the longest disputed border in the world.
India sent an infantry battalion and an artillery detachment up in reaction to the incursion in 1986 and a face-off ensued.
Colonel Pradeep Saxena (Retd.), who was with the 244 Medium Artillery Regiment deployed eye-ball to eye-ball against Chinese positions then, said, "The first Bofors 155 mm field howitzers that landed in our country were sent up there in January 1987, which I oversaw. Had the Chinese tried to move towards Tawang, they would have suffered such heavy casualties that it would have been a political embarrassment for them."
The stand-off slowly cooled down with both sides standing down.
When the late Rajiv Gandhi visited China in 1988, Deng Xiaoping, China's paramount leader shook the Indian prime minister's hand for three minutes, far longer than usual, and spoke of "forgetting the past", signs that China wanted an out from the conflict, which ultimately came about later.
Whether India and China will disengage in an equally matured manner across the Himalayas in today's context is, however, debatable.
Analysts point out that China has pulled ahead of India economically and in terms of diplomatic clout and the policy adopted by it is similar to its belligerent and provocative stand in the South China seas and the straits of Taiwan.
According to World Bank statistics, while China had a GDP of $14.722 trillion in 2020, India had a GDP of $2.622 trillion.
In terms of defence spending, China was again a colossus, spending $244.9 billion compared to India's $73 billion, as per SIPRI Military Expenditure Database 2020.
On the other hand, India has improved its military position, and domestic opinion may preclude any border adjustments.
Maj. Gen. Deb said, "In the larger context, the strategic contestation between India and China appears set to increase, with its fallout on all aspects of bilateral relations including the border issue."
At the same time, not just the soldiers who stand guard, satellites of all leading powers will continue to keep watch over the pass.
A mobile application -- HamGPS -- showed that at least a dozen satellites were hovering over Bumla -- which include not just Indian and Chinese but also Russian and American.