To be honest, I nearly didn't bother. The night before my foray into the uplands of Luzon, the second-largest island in the Philippines, I stop over in a village at the foot of the Cordillera Central ranges. I'm the guest of an old friend, who's just built a bungalow in this forest clearing with the money she earned working as a housemaid abroad. Amid the shacks, it stands out like a sore thumb - as do I; this is a place that doesn't see many visitors. A crowd that wouldn't disgrace a second-division football match surrounds me as I outline my idea.
The plan, I tell them, is to head for the remote tribal heartlands and meet a few of the 6.5 million people from 40 indigenous groups that still follow a traditional lifestyle on this archipelago of 7,107 islands. This is the cue for the curiosity on the faces of my hosts to cloud into concern. No, they haven't actually been to these places, but still... don't I realise the natives are "uncivilised"? Aren't I worried about getting kidnapped? Haven't I heard about the headhunters?
I brush aside their fears with an unconvincing shrug, then spend a troubled night listening to a dozen stray dogs howling at the fatefully full moon. By the time a hundred chickens start squawking at 4.30am, I still haven't thought of a way to wimp out without losing face. Instead, I draw some water from the pump well, wash from a bucket and board the Mountain View Liner - a grand name for the rusting boneshaker that's supposed to get me to the Kankanay settlement at Sagada.
"God Help Us", somebody has painted in large red letters above the driver, and it's soon clear why: the road tapers to a single track that endlessly twists back on itself as we make our way upwards, bouncing out of potholes and skidding over football-sized rocks. As we flirt with the brink of limestone gorges, heavy sacks of rice in the back of the bus slide queasily from one side to the other.
Thankfully, the scenery for the next six hours is as majestic as the route is exhilarating, as one hazy blue vista gradually overlaps with the next. Wild sunflowers vividly carpet the gaps between corrugated-iron-and-breeze-block villages, beyond which every olive-green mountainside is tiered with rice terraces. Having ascended this staircase to an ear-popping altitude of 3,000 metres, we finally step down into the rarefied atmosphere of hill-tribe country.
During the Seventies, Sagada could claim to be the Far Eastern outpost of the hippie trail. Today, despite a trickle of tie-dyed travellers, it's still a conservative community. A list of dos and don'ts handed out by the tourist office insists on "proper attire" and prohibits "embracing" outside of hotel rooms. There's even a 9pm curfew - signalled, somewhat forcefully, by a volley of gunfire across the valley. After the jarring journey, I'm more than happy to observe it, and check in to a deeply hushed pine-panelled cabin at St Joseph's Resthouse.
Next day, I step out into a chill and dazzlingly clear Cordilleran morning and wish I'd brought warmer clothes. At first sight, this could be any Filipino village - a single, nameless main street filled with honking 4x4s and the familiar cast of harassed women, basketball-bouncing children and toothless old men. However, the details that distinguish the locals from the lowlanders are apparent on closer inspection: for one thing, the dialect I'm hearing would be incomprehensible even a few miles from here. Moreover, many people are chewing languidly on betelnut leaves, a habit preferred to smoking. And there's dog meat for sale on a street corner - something else that makes me feel a long way from home.
Perhaps it's like going to Scotland and expecting everyone to be wearing a kilt, but I'm sad to see little sign of a tribal dress code, and instead plenty of jeans and baseball caps. Traditional dress, I'm told, is reserved for special occasions. By pure chance there's one this morning: the air suddenly swells with the sound of snare drums and xylophones, and a school band marches into view. Bearing flags and dressed in crimson Kankanay berets and capes, they're followed by a snaking line of fellow students in immaculate uniforms. Curious to find out what's going on, I track them down a forest path and out onto an overgrown playing field, where they form into neat ranks.
This, it turns out, is a sports day for the schools of Mountain Province, aimed at identifying the stars of the future. Before the fun can start, upwards of a thousand schoolchildren solemnly raise their right hands and sing the national anthem as the Philippine flag is hoisted up a bamboo pole. Then, in an inspired touch, a flaming torch is relayed round the field to rising cheers, and the Sagada Olympics is declared open.
As the games begin, I embark on a different form of exercise - a trek through Echo Valley in the company of Arturo, a local guide. Here we find the most striking evidence of a unique way of life, or rather death: although most indigenous groups share the faith of the overwhelmingly Catholic majority, their funeral customs can be radically different. High above us, suspended on wires in swirling clouds of fog, are a dozen or more "hanging coffins" - exposed to the elements, as Arturo explains, "to allow the spirit to escape to the next world".
We find 137 more tree-trunk coffins stacked like boxes in the gaping mouth of Lumiang cave, where Arturo surprises me by dragging one into the light and casually flipping off the lid. The occupant, partially wrapped in red-and-white woven fabrics, is tucked into a foetal position, hands raised in apparent horror at our intrusion. I can't help noticing that he or she has remarkably well-preserved skin: this particular body was mummified according to the tribal method of being placed in a high chair and smoked over a fire for 12 days. Mumbling inadequate apologies, we replace the oak plank.
This brush with mortality reminds me of head-hunting, the method by which young tribesmen once appealed to potential brides. "People inter-marry these days, so it's not a problem anymore," Arturo assures me. "However, it can sometimes happen in disputes over things like water resources. There was a case here about 10 years ago."
So much for how native people die. To see how they live, next day I visit the pleasantly purposeful town of Bontoc, where the impressive Kadchog rice terraces, built by the tribe of the same name, are skillfully shored up with boulders to conserve water. I arrive just as the workers are returning from the fields, and accompany a few to the inevitable karaoke bar.
Filipinos are the undisputed crooners of Asia, and competition for the microphone is keen. Nobody can sing, nobody cares and everyone has fun.
There's more evidence of the easy familiarity between people in this region on the ride back. It's packed as usual, and I'm struck by the instinctive manner in which people scoop up and take responsibility for each other's children. Just as I'm remarking how everyone seems to belong to one big family, an apple-cheeked two-year-old boy underlines the point by loudly insisting I'm his father - much to the embarrassment of his mother and the amusement of her seven other children.
The return journey to the lowlands involves another long bus journey, and this time I stop off at random in the Ibaloi village of Sayangan, perched near Mount Timbac. Having put away a large plate of steamed vegetables, salad and tilapia fish (for about £1), I decide to stroll around the farm that dominates the slopes overlooking the village. In a misty field of cabbages, I meet a group of women coming back from church in Ibaloi outfits of strident red-and-black jackets and skirts (and very un-traditional wellies). They ask me where I'm going, and I tell them Manila. "Oh, you don't want to go there," they advise me. "It's like another world altogether." I have to agree they're absolutely right.
There are no direct flights between the UK and the Philippines. Airlines such as Qatar (020-7896 3636; www.qatarairways.com), Cathay Pacific (020-8834 8888; www.cathaypacific.com) and Gulf Air (0870 777 1717; www.gulfairco.com) fly to Manila via their hub cities.
Sagada is about 275km north of Manila and can be reached by bus from Baguio.
To reduce the impact on the environment, you can buy an "offset" from climate care (01865 207 000; www.climatecare.org). The environmental cost of a return flight from London to Manila is £24. The money funds sustainable energy and reforestation projects.
St Joseph's Resthouse, North Luzon (00 63 918 559 5934). Cabins from $27 (£15).
Embassy of the Philippines (020-7835 1100; www.wowphilippines.co.uk).Reuse content