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Searching for the source of Papua New Guinea’s longest river

  • Written by  Charlie Walker
  • Published in Explorers
Thomas aims a slingshot at a bird of paradise for its decorative feathers Thomas aims a slingshot at a bird of paradise for its decorative feathers
04 Feb
Applying Western geographical concepts to distant lands isn’t always a straightforward pursuit, as Charlie Walker discovered during a quest to locate the remote, unmapped source of Papua New Guinea’s longest river

We left the lush coffee gardens and began to climb. A tangle of hanging vines, knotted undergrowth and barbed tree trunks pressed in on either side of a path worn by generations of bare feet. Kephas, a primary-school English teacher, led the way. His broad feet and spreading toes gripped the ground while his two-foot machete trimmed back the jungle. In his wake, my ankle-high boots were heavy, noisy and clumsy, slipping every few steps on the monsoon-washed trail. Behind me was Philip, the coffee farmer whose small plantation we had just walked through.

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We were setting out on an attempt to climb Mount Yumbulum, deep in the Finisterre Range. The third-highest peak in Papua New Guinea (4,155m), Yumbulum (the name given to the mountain by some locals, though it is also known as Boising and Gladstone) was the start of a journey during which I aimed to reach PNG’s three highest peaks and locate the unknown source of its longest river, the Sepik. 

The two highest peaks are climbed semi-regularly but this third mountain was an unknown. My companions were vaguely aware of ‘Yumbulum’ but had never seen it. A series of steep jungle ridges hid it well. However, Kephas and Philip seemed excited to accompany the tall, pale foreigner who had traipsed into their village, Intsi, the previous evening.


I had dreamed of visiting PNG for a decade. It represented the end of the world to me – a final frontier on the liminal fringe of Western consciousness, a place where cannibals and headhunters once jostled for existence in the densest tangle of equatorial rainforest. 

Of course, the practice of cannibalism has now ended. The headhunters have hung up their bows and the outside world has made some inroads, but large tracts of jungle, mountain and swampy river remain home to those living much as their ancestors have for 40,000 years of geographical isolation. I unabashedly aimed to be a voyeur peering through an eight-week window onto their world. The peaks and river source were merely a framework on which to hang this desire.

For three days, we snaked up and down trails invisible to me. Without Kephas’s keen eye and busy bush knife, I wouldn’t have got far. Several times, we climbed 1,000 metres, only to descend as much. 

CW 3View of Mount Hagen from the slopes of Mount Giluwe

The monsoon was at its zenith. For half of each day, downpours drummed deafeningly on leaves and I halted frequently to pluck swelling leeches from my shins. Philip and Kephas each used a banana leaf for an umbrella, but I required both hands to reach for support when I slipped. Often as not, what I grabbed was thorned. Each evening, I spent half an hour with tweezers, picking spines from punctured palms.

In a clear dawn sky on the fifth day, Yumbulum jutted above the treeline, just a few miles distant. But Kephas approached with a sombre expression. 

‘We go back now. We go home,’ he said.

‘But we’re nearly there,’ I replied.

‘No more villages. No more trails. Too cold up there. And the spirits don’t like it. It is home to them, not us.’

Without their guidance and jungle savvy I was lost. I resigned myself to retreat. It was probably for the best. Taking my shoes off the previous evening had revealed a slightly rotting foot in a blood-soaked sock. The distended body of a glutted leech lay between two toes. 

CW 5A hunter encountered on a footpath in Hela Province

Upon our return to Intsi, I stayed with Philip’s father, John. After dinner, he handed me something and asked if it was gold. I scrutinised the muddy metallic hunk, half the size of my fist. It confused the needle of my compass and was clearly not gold. John was crestfallen when I told him. ‘You’re a geologist?’ he asked in his singsong English. I shook my head. ‘That’s a shame. We have gold in these mountains. It is waiting to be mined.’

Mining is big business in PNG. I later passed through a mountain village close to Ok Tedi, the country’s largest mining operation. A group of young men stood beside the airstrip waiting to be flown to the mine for 14 days of hard labour. Despite New Guinean miners being among the lowest paid in the world, they become rich men by village standards and no longer partake in subsistence farming.

Mines, however, are finite. Ok Tedi predicts fewer than ten years of future operations. By then, a generation of men will have forgotten their traditional way of life. This is already fuelling a drift to urban centres, where unemployment is more than 50 per cent. The resultant gang culture has led to unrivalled levels of alcoholism, crime and sexual violence. I hoped for John’s sake that the longed-for geologists never came.

The other two mountains were mercifully less resistant to my approaches. I sat atop Mount Wilhelm (4,509m) with a dawn panorama reaching to the sea on both sides of the island. Stacked clouds soon marched inland with lightning forks slashing through them. Their flashing underbellies reflected a silver thread off the Ramu River. 

CW 6Johnny shows off one of his pigs in Kopiago village

A few days later, I reached Mount Giluwe’s rocky summit (4,367m) atop a mist-swathed alpine grassland that seemed more Caledonia than Melanesia. After a shivery sleep above the treeline, I descended into moss forest, where the night’s moisture oozed from green-furred trees and sunlight filtered through rising steam in a jade-tinted haze. It was ethereal and I was sad to descend lower into the claustrophobia of regular jungle.

From the end of the Highlands Highway, PNG’s only significant road, I began my westward trek towards the Sepik’s source. I didn’t have exact coordinates, but it lay roughly 50 miles away, hidden in a vast rainforest.

It was a two-day walk to Kopiago, where I was invited into the home of Johnny, whose 20 pigs snuffled around the garden. Johnny was clearly a wealthy man. Pigs are the ultimate status symbol and the favoured currency for buying wives, of which men take as many as they can afford. 

Nearby was a hutch containing a cassowary. The chest-high bird peered at me through a gap between wooden slats. Given their ability to kill dogs, and even people, it’s hardly surprising cassowaries are kept well caged. 

For three more days, I walked village to village on muddy trails, passed like a baton between a succession of charming guides speaking Tok Pisin, the only common tongue in a nation of more than 830 languages. 

CW 9Eckhart lights up in the Strickland Gorge

I finally broke out of the forest and into a gorge: a dramatic gully of yellow grassland with the Strickland River rushing along its floor. I’d heard there are no bridges over the Strickland and I would have to paddle across. It was 50 metres wide and despite the river’s obvious speed, the water looked flat and safe.

For 15 miles, the Strickland ran west towards the Sepik before veering away to the south. While inflating my packraft, I decided to float westwards as far as the river would allow and save myself some walking.

With my backpack strapped to the front of my tiny craft, I ventured into the current. The water was faster than expected. Within five minutes, I’d rounded two bends and was racing towards white water spuming between boulders. Midstream and with no time to reach the bank, I could only face the rapids and brace. 

I dodged the first couple of breaks but collided with the third and narrowly avoided capsizing. Water sluiced across my spray deck but the river flattened once more. I was exhilarated. But the river cornered again, narrowed and quickened. More rapids loomed. I was tossed left and right, then pitched deep into a trench, submerged. Seconds later, I saw sky for an instant before being dragged under again and rolled around some more.

I was pinballed down three more gauntlets before finally regaining the bank, cold, drained and scared. With renewed caution, I nosed downstream a few more miles until shrieks suddenly sounded from the riverbank. Figures emerged from the trees, arms waving frantically. I pulled into an eddy, where my raft was seized upon by half a dozen shouting men. One was louder than the rest: ‘It’s not good! Him big river…bad river. Big water there!’ He flailed his arms and spun his eyes up into their sockets, a pantomime of my death by drowning. 

CW 14Charlie Walker on the grasslands of the upper slopes of Mount Giluwe

I climbed onto the rocks. There were handshakes all round before it was explained that the river soon entered a canyon and plunged underground for a mile. I had escaped just in time.

The men’s village was a day’s walk away. They came to the Strickland to pan for alluvial gold washed down from the Porgera mine 100 miles upstream. The mine has produced more than 500 tonnes of gold since operations began in 1990 and has dumped its tailings untreated into the river. These tailings are said to have poisoned the water and fishermen report ever-lower catches. 

Meanwhile, the panners rarely find more than a few specks of gold dust, which they sell for around £10 per gram; roughly a quarter of the global market rate. They said their wives could manage without them in the village and their camp had the feeling of a boys’ club. They were currently building a bridge to suspend across the river. Great cables of bundled vines were laid out among the trees. There was a village somewhere on the other side. Apparently, there had been a bridge until a cross-river raid a month earlier. Traditional spears, bows and arrows were supplemented with machetes.

‘Me chop a fella’s hand off!’ boasted one of the group. 

CW 4

In the lingering mists of morning, I left the gorge, guided by Eckhart and Yiston. Gaining 1,500 metres, we walked non-stop for ten hours. My companions strolled effortlessly before me, puffing marijuana as they went. 

Late afternoon, we reached Bak. The village sat on a wonky plateau at the head of a valley. All around stood tall, jumbled mountain peaks swimming in and out of cloud. Eckhart and Yiston deposited me with the sole policeman, Maroons, who told me how hard it was to police the huge, roadless area he alone was tasked with. When crimes were reported, he went to investigate but the perpetrators simply melted into the jungle. 

‘Just last month I went down to the river as there was a fight,’ he said. ‘A man’s hand was chopped off but I never found out who did it. They all fled when I arrived so I cut down their bridge and walked home.’

Maroons’ job was apparently to fight a losing battle in the project of imposing Western-style law and order on a land with a millennia-old tribal-justice system.

For the final leg, I was accompanied by two perpetually smiling, chest-high men. Yoksie was 19 but looked 30 and Thomas, a devout Baptist, was 30 but looked 50. For several days, we passed no villages, climbing high through moss forests in stubborn drizzle. We passed through an eerie area of volcanic craters filled with heavy mists. Yoksie called it the Ice Land. 

‘My father died up here,’ he said. ‘There are many spirits living here.’

The night we spent at altitude was a cold one. A sheet of bark formed the roof of our improvised shelter and we slept like sardines with my unzipped sleeping bag spread across us. At 3,200m we reached the mountainside where my satellite research had pinned the furthest source of the Sepik, but it turned out the whole rotten flank of Mount Wamtakin was one enormous tilted bog, underlayed with foul-smelling mud. The marsh seeped idly southwest and at some indistinguishable point became the Sepik’s headwaters. 

We squelched downhill for a few hours until we chanced upon an abandoned bivouac, collapsing but serviceable. Thomas disappeared for a while before returning with a bunch of wild watercress, which we cooked into a smoky-tasting soup. Over dinner, Yoksie expressed confusion at my search for the Sepik’s source. To him, the river was a living thing, forever shifting and unobservant of humanity’s rules.

Perhaps the concept of pinpointing exact coordinates was yet another arbitrary exercise in applying Western ideas to an ancient land more elusive than we’d like.

Charlie Walker is a travel writer and adventurer who specialises in human-powered journeys. Among other places, his expeditions have spanned the Tibetan Plateau, Mongolian steppe, Congolese jungle and Arctic tundra. He has travelled more than 50,000 miles by bicycle, foot, horse, raft, ski and dugout canoe. 

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