"Hunza is a powerful place," says Ejazullah Baig, letting his eyes linger on the winding silver thread of the Hunza River. "It's the water that gives the valley its power. And not just the fact that it's clean water. Clean water won't make you sick but it won't cure you if you're sick either, or keep you young."
On one of Karimabad's serpentine streets below, an old man with half a dozen breeze blocks strapped ingeniously to his back walks towards us, winding his way up the steeply inclined cobblestones, step by careful step. The blocks must weigh 60kg but he doesn't seem to mind.
"That's Anwar Shah," says Ejazullah, smiling warmly. "He's more than 80 years old."
It's hard to tell Ejazullah's age. The wiry curator of the historic Baltit Fort Museum could be anywhere from 30 to 50. But he's not talking. "What does it matter anyway?" he says, feigning innocence. "I feel like a teenager! Age doesn't matter in a place like Hunza; that's part of its magic."
Indeed, the Hunza Valley in the soaring northern mountains of Pakistan's Gilgit-Baltistan province is chock full of magic, and considerable mystery. For decades, it has perplexed and amazed people as much by its sublime beauty as its reputation for keeping people young.
James Hilton's 1933 novel Lost Horizon, set in the mythical alpine utopia of Shangri-La where near-immortal people live in peace and harmony, is reported to be based on Hunza (the author visited the valley a few years before the novel was published). Some people also believe it is the historical Garden of Eden, where Adam and Eve lived a life of eternal youth before they were unceremoniously thrown out. Others argue it was here, or somewhere nearby, where Gilgamesh, the Babylonian warrior-king and prototypical hero from antiquity, found - and lost - the secret to eternal youth.
Nearly 5,000 years later, Ejazullah tells me some of the power that slipped through Gilgamesh's fingers remains. He shuffles his feet to face another of Gilgit-Baltistan's valleys, Ultar, a narrow gorge rising northward up into the permanently snow-capped mountains of the Karakorum range. "Up there is the source of Hunza's magic," he says. "It's where Gilgamesh went to find the old couple whom the gods had blessed with the secret to eternal life. But if you want to find that secret, you'll need to do more than follow in his footsteps. The secret to health in Hunza is locked there but it takes a serene mind to unlock it. And here's the thing: serenity is a rare thing in this valley these days. The magic you're looking for is almost gone. Hunza is dying."
Just my luck. The mystery of eternal youth still haunts me, as it does just about everyone else in the world, as it has for - well, forever. Biologists continue to chase after that ultimate Holy Grail, digging deeper into the mysteries of genetics to find the proverbial switch that turns off the ageing process. A scientific paper published in this year's January 6 edition of the science journal Nature reported that researchers at Harvard Medical School had managed not only to turn it off but also to reverse the ageing process altogether in mice. There's still a long way to go before the same technique can be applied to humans, the authors of the study said, but they are hopeful.
Still, and ignoring the ethical issues involved with messing about at such a basic level of human existence, scientists agree that stopping, or even reversing, the ageing process in itself will not ensure the vitality of eternal youth. We still have to stay healthy and battle disease - who wants to live forever if it means being condemned to bodies that slowly succumb to the cumulative ill-effects of eternal life? We are not gods, right?
No, we are mortals, living in a mortal world where the quest for eternal youth rages on, with the age of science inheriting the mantle from the age of warrior-kings and magical fountains. Neatly packaged elixirs now promise what springs hidden in the vast unknown of the primordial Earth once did. Only now, you don't have to be Gilgamesh, climbing mountains or battling beasts to get it. They're available to all, in simple, non-oily applications and easy-to-follow methods.
None of them actually works, at least not forever. Despite all of science's impressive accomplishments, we humans still age as we always have, steadily decomposing into flabby, toothless creatures wandering the world half-deaf and half-blind, desperately seeking ways to prolong our lives.
But in Hunza, it's different. If an octogenarian can carry 60kg on his back, uphill, and barely break a sweat, there must be something to the valley's claims on youthfulness. And the superlative health of the Hunzukuts has also been well-documented: a 1960s expedition to the valley by two western cardiologists carrying a battery-powered electrocardiograph found zero heart problems among the 20 men they tested between 90 and 100 years old. Around the same time, an optometrist, intrigued by stories recounting the health of the Hunzukuts, made his own journey and found, to his shock, "that everything I had read about perpetual life in this tiny country is true. The eyes of some of Hunza's oldest citizens are perfect".
So what is Hunza's secret? And what does Ejazullah Baig mean when he says it is dying?
Well, Hunza is dying - it's literally falling apart. Dr Kenneth Hewitt, professor emeritus in the Geography and Environmental Studies department at Wilfrid Laurier University in Waterloo, Canada, and an expert on Pakistan's northern geography, told me last year that the ground beneath Hunza's feet is melting. "One of the vulnerable aspects of high-altitude regions is permafrost," he said, trying to draw the world's attention to the approaching disaster. "Areas like Hunza are more susceptible to melting permafrost because of global warming, which raises the danger of landslides significantly."
Over the past 10 years, Hewitt has observed four major landslides in the region, the latest a massive one in January 2010 that swept away an entire village and created a dam on the Hunza River 20km upstream from Karimabad, Hunza's historical capital, forming a giant lake that submerged more villages. The lake, visible on satellite images, remains to this day. But if the natural dam collapses - which most inevitably do - it could send a giant wall of water 40 metres high raging down the valley, destroying everything in its path. And, as winter temperatures continue to rise, Hewitt expects more massive landslides in the near future, with accompanying death and destruction.
If Hunza crumbles, the secrets to its vitality will crumble with it. It would be a sad loss for the valley's former queen, Rania Attiqa. Seated regally in her modest castle in Karimabad, surrounded by portraits of dead kings of the former independent monarchal state that was formally absorbed into Pakistan in 1974, she speaks like a person who has an enduring respect for the powers that define life in the valley. "We don't know the language of the mountains," she tells me. "We can't understand the language of the glaciers. We used to respect those powers but now little of that respect is left."
For Attiqa, Hunza has become another victim of the modern world. A generation ago, before the Karakorum Highway was built, linking Pakistan to China, life was simpler, she says. "It was a time of magic. People believed in djinns and faeries; they believed in working hard and living simply. But after the Karakorum was built, the trucks came, with their pollution and their noise and their processed foods. They changed life here. They chased away the faeries. You can still find them, of course, but you have to go further up into the mountains, to the serene places."
There's that notion again: serenity. It seems Hunza's magic is tied to it somehow. But there's not much serenity left in Karimabad these days. The danger of flooding if the artificial dam collapses is one source of tension. The population explosion, partly caused by the Pakistani government's promises to develop the region into Pakistan's tourism Mecca, is another. There are now about 10,000 people living in the Hunza-Nagar district, and about 5,000 of them in Karimabad. New roads have been built, and new hotels crowd the town's narrow streets. They're largely empty, however, victims of Pakistan's instability that keep tourists away.
The resulting anxieties are having their effect: the phenomenon of longevity is fading, along with the magic Attiqa says is the first victim of development. Ten years ago, the Baltit Fort Museum used to proudly show slide shows of Hunza's ultra-elderly, Ejazullah tells me. Not any more. But there are still people in Karimabad who remember the good times. On any given day you can find them, seated in small groups beside their hand-carved wooden canes, soaking in the late afternoon sunshine, the elders of the village exchanging stories of life before the fall.
"When I was a child, Hunza was heaven," says Alip Shah, an 80-year-old who has spent his entire life in Karimabad. "There was no theft, no criminals, no crime at all. The people still believed in the power of the mountains, they still honoured that power. Now the only power that matters is money."
His companions - one more octogenarian, a 90-year-old and a relatively youthful 63-year-old - nod gravely. Hunza has changed, they all say.
Historically, Hunza has been a place where locals depended on what they grew to survive. Its traditional cuisine is a health buff's complete guide to nutritional well-being: a frugal, all-natural, trans-fat-free diet of fresh fruit and vegetables with the occasional treat of meat.
"In the past, there were no worries in Hunza," says Ghazi Johar, the 63-year-old. "There were no rich, no poor. Everyone was equal. Now some are rich, some poor. The rich want to be richer and the poor envy the rich. The community is divided."
The stresses that come with disunity are playing havoc in the valley. Heart disease is up along with other stress-related health problems. Hunza's medical facilities, funded by the Agha Khan Development Foundation, are some of the best in Pakistan, but still the people are dying younger.
Modernity can be a double-edged sword and the progress Hunza has seen in just the past decade has been phenomenal. In 2002, the only internet connection was a satellite feed at one of Karimabad's few hotels, which worked occasionally at best. Now a new internet cafe keeps local youths glued to computer monitors for much of the day. Many of the newer hotels have their own connections, providing a glimpse of the World Out There in glittering visions of what awaits those who embrace the modern.
Hunza is now plugged in to that world, including all of its passing fads. It's a world where the "new and improved" bombards our senses as the prevailing mantra for the masses. In it, part of it, connected to it we turn time into a powerful engine that drives us forward to the next horizon. Nothing is eternal in that world, and certainly not youth.
What's being lost is what the world is sorely lacking: the wisdom acquired by simple folk such as the Hunzukuts.
Still, "it's not completely lost," says Ejazullah. In addition to being the Baltit Fort Museum's curator he is also a mystic healer, unlocking the secrets in Hunza's water to semingly cure ailments ranging from coughs to psychological breakdowns. "The people are under stress and that stress is manifesting itself in physical ways. Hunza is off balance and my healing practice tries to restore that balance. If nothing else, I'm giving them hope, removing their fears, steadying their desires and making them aware of their place in existence. This is the key to healing."
Indeed, what Ejazullah is describing is just what many sociologists have known for years: happiness is not necessarily tied to wealth or the accumulation of material things. Contentment, the feeling of well-being that can shed years off our ageing bodies, is, according to studies such as the UN Human Development Index, the product of our own self-awareness and the ability to be at peace with that awareness.
Walking through Karimabad's idyllic orchards, I now start to get a sense of what Ejazullah means when he says Hunza is dying. It's not important whether the fountain of youth actually exists. Even if it did, I must admit that I don't possess the kind of serenity Ejazullah says I need to unlock its secrets. But I will go up the Ultar Valley in any case, not to chase Gilgamesh's dream of living forever, but to participate in Hunza's magic, and maybe see a few faeries while I'm there.