On one side, the palm-sized rock was smooth, flat and uninspiring, but turning it over revealed a hypnotic swirl of circular patterns criss-crossed in ribs. It was the fossil of an ammonite, and scattered haphazardly across the ground around me were others. An ammonite is a type of a long-extinct marine mollusc that disappeared from planet Earth about 65 million years ago. So, what was it doing in this unlikely spot 4,000 metres above sea level?
That I was able to hold in my hands signs of life from the age of the dinosaurs was remarkable enough, but what made it even more astounding, was the realisation that the spot at which I now stood had once been the bottom of a tropical ocean. I took in a deep, laboured breath, and looked around me at towering sandstone cliffs rising hundreds of metres. They were pocked with caves like some kind of fairy fortress. Some of these caves had frayed old rope ladders leading up to them, and inside were galleries of ancient Buddhist art. Above and beyond these castles of sand were the black frozen walls of the Himalayas.
The story of the formation of the Himalayas, and the reason I was holding a marine fossil in my hand, is all to do with plate tectonics. About 50 million years ago, the northward-moving Indian plate crashed into the Asian plate, and in the process, formed a belt buckle of mountains that now stretch (as the Himalayas and neighbouring ranges) halfway across Asia. The desolate, wind-blasted valley in which I stood had once been at the bottom of the sea that had separated India from the rest of Asia.
We were in Nepal's Upper Mustang region and halfway through a three-week trek. A restricted area requiring special trekking permits, Upper Mustang is a little thumbnail of Tibet in Nepal. Unlike Tibet itself, where the Chinese have done much to suppress traditional Tibetan culture, in Upper Mustang, the culture has been allowed to thrive. After several days walking through desert canyons where the rock is tinged with natural primary colours, we'd reached the near mythical walled "capital" of Lo Manthang. With its narrow alleyways, high whitewashed walls and numerous monasteries painted in blood red, this is a town of dreams. A town where red-robed monks read from 100-year-old parchment texts, where wild-faced nomads gallop up to the city walls on white stallions, and where a royal family still lays claim to the central palace.
From Lo Manthang we’d walked southward again through a landscape of wrinkled cliffs with fluted chimneys and past oases of poplars coming into leaf. We hadn’t just walked with single-minded focus, though. We’d allowed time to be tempted off the main trail by minor side paths that led to high-altitude yak pastures. We’d visited cavelike Buddhist monasteries where the air smelt of burning juniper. We’d ridden stumpy and hardy mountain ponies over grasslands where marmots stood on sentry and blue sheep scarpered up distant scree slopes. We’d sipped salty yak butter tea in the black felt tents of Tibetan nomads and followed scientists as they’d scoured remote valleys looking for signs of one of the most mythical of Himalayan creatures: the snow leopard.
Eventually, we'd crossed a half-dry riverbed full of ammonites and then clambered right up into the mountains themselves, where we'd crossed dauntingly high passes and joined up with groups of other trekkers on the popular Annapurna Circuit. Then we'd veered westward to the remote, half-frozen Tilicho Lake before crossing down to the regional centre of Jomsom, via a difficult, rarely trekked pass that had required ropes, crampons and basic mountaineering skills. Although we traversed many different landscapes and climate zones and met a broad cross section of people, the stories they told us were always laced with a sense of the impossible.
Even that ammonite I'd held in my hand had been rich in Himalayan folklore. A couple of days after picking up the fossil, we found ourselves in the Muktinath temple complex. Like so many places in the Himalayas, Muktinath is holy to both Hindus and Tibetan Buddhists. The reason for this reverence is the presence of an eternal flame, 108 sacred water springs and the numerous shaligrams, or ammonites, found in the area, which are considered a representation of the Hindu god Vishnu. One of the most important pilgrimage spots in the Himalayas, Muktinath attracts scores of people every day. Lakshmi, a bearded Indian sadhu (holy man), whom I met at the temple, was one of the more devout. "About 35 years ago, when I was around 12 or 13," he explained to me, "I left home and started travelling from one holy place to another. I haven't seen my family since I left, but I don't believe in blood relations, so I'm not bothered."
I asked him about some of the places he'd travelled to. "I've been all across India, Nepal and the Himalayas. I spent many years living in a cave and meditating at the holy Mount Kailash on the far side of the Himalayas [in modern-day western Tibet]. In the end, though, I left. There are too many people there now. Too many soldiers, too many police. It was time to move."
The faith that drove Lakshmi to turn away from his family, along with his story of adventure, might seem extraordinary to most of us, but some Himalayan tales require an even bigger leap of faith. Two of our baggage porters were brothers, and one evening, after a long eight hours walking, we set up camp inside a small stone-herder's hut. After dark, as the temperature plummeted, we all huddled together and shared stories.
The conversation soon moved on to ghosts and magic, and one of the brothers told us about a man in their village who had the ability to transform himself into a type of wildcat. In this feline form, the man would slip like a spirit though the moonlit hills, attacking and eating livestock. In the mornings, he would be found back in his house in a deep sleep with blood-stained hands. Everyone in the village knew about his power, but nobody really knew what could be done about it. Eventually, the man died, but, so the brothers insisted, one of his sons has inherited the same powers and the slaughter of livestock continues.
I'd been ready to dismiss the brothers' story as just another tall tale, but then, on the last day of our trek, I saw with my own eyes an object so unlikely, it defied reason. We'd arrived at our camping spot in an alpine meadow after dark and thought that we were the only people there. But, when we woke up on that final morning, we discovered a number of temporary- looking wooden structures and some ancient, weathered tents nearby. The occupants were just waking up as well. A ragtag-looking lot, they weren't trekkers, shepherds or holy men. They were treasure hunters. The treasure they were after, though, wasn't of the gold and rubies sort. No, the thing these men and women were after was even more valuable.
One of the men in the camp called me into his hut and, opening a small cloth bag, he revealed something remarkable: a handful of dry, shrivelled wormlike creatures. It was yarsagumba; half-animal, half-plant, a bizarre fusion of a caterpillar and a parasitic fungus. Highly valued in Chinese traditional medicine as an aphrodisiac, yarsagumba is worth more than its weight in gold, and every year around June and July, hundreds of Nepalese leave their villages to head up into half-frozen alpine meadows in search of it. And if a caterpillar can be a treasure, and the Himalayas the floor of an ocean, then who is to say that up here, in these oxygen-depleted heights, people cannot turn themselves into cats?