The unsolved mystery of Skeleton Lake

Nearly 80 years after the Himalayan lake first captured the world’s imagination, the mystery continues to confound – even as revolutionary advances are made in understanding our past.

The rising sun was yet to shine on the freezing, snow-covered cirque where I was resting after an early morning trudge to a glacial tarn. Cold and miserable, at a dizzying height of 4,800m in the Indian Himalayas, I couldn’t summon the energy to care about the pile of human skeletons stacked next to the frozen lake known as Roopkund. In 2009, when I went on the trek, the mystery of “Skeleton Lake” was considered solved and Roopkund trek was well on its way to changing the course of the nascent trekking scene in India.

However, more than a decade on, not only has the small lake become a victim of its fame but it continues to confound even as revolutionary advances have been made in understanding our past.

In 1942, H K Madhwal, an Indian forest official, stumbled upon hundreds of human skeletons stockpiled in and around Roopkund lake. He reported the bizarre find – a mysterious lake where between 300 to 800 people met their tragic end – and the frigid Himalayas continued to preserve the human remains. In the late 1950s, the macabre mountain find was announced to the public, raising great interest and triggering several investigations that continue to date.

All of that was only secondary to scores of trekkers who, like me, have trekked to Roopkund in the last decade, chiefly enamoured by the unparalleled views, diverse landscapes and challenging route.

Situated five days from the nearest settlement in Uttarakhand state, the week-long trek spanning more than 50km sets off from idyllic Himalayan villages that are no more than a cluster of traditional houses. Passing through ethereal mist and moss-covered oak forests, the trail then winds along expansive wildflower-laden alpine pastures, locally known as bugyals, that occur only above the height of 3,300m in the Himalayas. Lofty Himalayan peaks soon come into view and dominate the horizon for the next couple of days. The highest point of the trek at 5,000m is Junargali, a knife-edge-like ridge with a 360-degree view of the high Himalayas and the rugged glacial landscape.

Roopkund lies 200m below this ridge. The treacherous, steep climb to Junargali has led to a running joke among trekkers that one wrong step could easily add more bones to the existing pile in the lake. Nearly 80 years after Skeleton Lake first captured the world’s imagination, that simple joke doesn’t seem too far-fetched after recent revelations.

Initially, the skeletons were thought to belong to Japanese soldiers or Tibetan traders on the Silk Road who died due to either an epidemic or exposure to the elements. Later, after forensic analysis in 2004, the best theory was that a group of Indian pilgrims, both men and women, assisted by local porters from the region, were struck by giant hail at Roopkund in a single event in the 9th Century, so concluded from the perimortem injuries on the skulls.

They were believed to have been on a revered, once-in-a-12-year Hindu pilgrimage called Nanda Devi Raj Jat Yatra, an ancient tradition that continues to this day. Roopkund is on the way to Homkund, the final destination of this arduous foot journey.

Veena Mushrif-Tripathy, professor of archaeology at Deccan College in Pune, was part of the 2004 investigation. She recounts the team concluded the pilgrim theory as most plausible as there were no weapons at the site, indicating the cause of death was not an attack and that they were not soldiers. They also found remnants of musical instruments, and there were old folk stories of pilgrims travelling on the Nanda Devi Raj Jat Yatra. The DNA analysis, Mushrif-Tripathy said, revealed it was a male-female group belonging to a wide age range, further strengthening this hypothesis.

When I trekked to Roopkund, a crude reduction of this theory was given as an explanation for the bones. We were also regaled with fantastical tales of angry goddesses, irreverent pilgrims and dancers turned to stone. Every campsite, every pond and so many other landmarks on the way were imbued with elaborate folklore. This heady mix of awe-inspiring nature and riveting mythology turned the morbid Roopkund into an enchanting curiosity.

It isn’t surprising, then, that Roopkund inadvertently drove the rapid commercialisation of the Indian trekking scene. In 2009, a Bengaluru-based company launched an affordable group trek to Roopkund that could be booked online. The IT boom in India had led to rising disposable incomes that coincided with the newly accessible slopes of the Indian Himalayas, which until that point had mostly been only explored by hardy alpine types.

Predictably, Indian trekkers flocked to master the difficult yet highly rewarding Roopkund trek. Following this success, similar companies mushroomed across the country, popularising more trails across the Himalayas to meet the flourishing demand, later bolstered greatly by the rise of social media. Unfortunately, the downside of this commercialisation has been much environmental degradation in the Himalayas. Today, the same Roopkund trek that got Indians onto mountain slopes like never before is now inaccessible due to a government ban on camping in the much-exploited, ecologically fragile bugyals.

A year after my visit, in 2010, the first ancient-human genome was sequenced, quickly revolutionising how we study our past. Soon, the Roopkund mystery was once again resurrected. Thirty-eight powdered bone samples prepared from skeletal remains stored at the Anthropological Survey of India, Kolkata, were sent to 16 labs worldwide for genomic and biomolecular analysis. The results of the five-year-long study, published in 2019, stunned the world.

The new study found that the 38 skeletons belonged to three genetically distinct groups and were deposited at the lake during multiple events over a 1,000 year period. There was a South Asian group, predictably, whose bones were deposited between the 7th and 10th Centuries in multiple events. The team also found a new group of individuals of eastern Mediterranean ancestry originating in the island of Crete, who died in the 19th Century in a single event. And there was one sample that had South-East Asian origin, also from the 19th Century. Surprised by this anomalous finding, the team then did a dietary analysis to see if it supported the results of DNA analysis, and it did.

“At a site like Roopkund where the context is highly disturbed and the possibilities of full-scale excavations are low, using aDNA [Ancient DNA] provides us with direct information about the genetic ancestry of these individuals,” said Ayushi Nayak from Max Planck Institute for the Science of Human History. “Our 2019 paper was able to add new kinds of data through different biomolecular methods.

The new evidence pointing to the presence of groups of non-Indian origin at Roopkund lake was a shock, as there isn’t any historical evidence to explain who these people were and what they were doing in the far reaches of the Himalayas. “Questions remain about the group of individuals that matched closest in ancestry to modern-day eastern Mediterranean people – in terms of their reasons for visiting Roopkund and whether they were European travellers or locals with eastern Mediterranean ancestry. Or about whether there are other sites in the region with such accumulations of human remains,” said Nayak.

As I remember my journey to Roopkund today, my mind reels as I comprehend the complexity of the mystery and the heavy legacy of the trail we trod upon so nonchalantly. Despite their intoxicating beauty on good days, the rugged high Himalayas can be deadly on bad days. Several have lost their lives in pursuit of Roopkund over the past decade.

But what were the motivations of all those, including the unexpected eastern Mediterranean group, who met their untimely end at this lake centuries earlier? I also wondered how they all died. Could some of them have fallen from the Junargali ridge, as we joked? Could some of them have been killed by exposure like we feared? Could some of them have died due to acute mountain sickness, which is all too common at this altitude? It is improbable that several distinct groups of people died at Roopkund over several separate incidents spanning more than 1,000 years due to hailstorms. And yet, that’s the only evidence we currently have.

“There are hardly six to seven skulls [with] trauma related to hail,” said Mushrif-Tripathy, who was also part of the 2019 investigation and a co-author on the latest paper. “According to me, the mystery is not at all solved. We have more questions than answers.”

The site remains highly disturbed and unpreserved. Over the years skeletons have been moved around by trekkers and even taken home as souvenirs, posing a challenge to finding an accurate answer in the future, despite potential advances in science. The 2019 study’s anomalous insights have understandably caused much flutter, but the more important consideration is that if an analysis of just 38 samples out of hundreds of bodies threw such a curveball, what other surprises are buried in the icy grave?

While we scratch our heads in bewilderment and wonder, the skeletons at the lake continue to confound. At Roopkund, the mystery of the dead lives on.