New Guinea's other half    Papua New Guinea's mirror image is a little-known land where Asia coexists uneasily with Melanesia

Like a huge prehistoric bird, the island of New Guinea hovers above Australia. Under the bird's breast lies an ill-explored region where snow-capped ranges fall abruptly towards the trackless forests and the pandanus swamps, down to the Arafura Sea.

West Papua, Papua New Guinea's mirror image, is a little-known land where Asia coexists uneasily with Melanesia. In Indonesia's easternmost province, formerly Irian Jaya, cultures collide as inexorably as the Australian and Asian continental plates which forced up the highest land between the Himalayas and the Andes.

Direct charter flights from Darwin in Australia’s Northern Territory now reach Timika, a boom town not yet shown on many maps. To the south-east lie the Lorentz Nature Reserve and the homeland of the Asmat, famed woodcarvers - and headhunters.

There are some drawbacks to arriving by the back door: many nationalities require a visa and there are few facilities for tourism in Timika. The good news is that you can sleep - in comfort and style - within sight of birds of paradise, and play a round of golf beneath the rainforest giants; or just observe what happens when Asia meets Melanesia.

I felt this was an opportunity to be seized - New Guinea without lawless raskols, Indonesia without too many cement-walled showers or squat toilets. That was I how I found myself queueing at two in the morning behind the chicken wire at Timika Airport, surrounded by a plane-load of matey expatriate technicians in jeans and tee-shirts. Close by stood the 84-bed Sheraton Inn whose timbered lodges perched on stilts, enclosed by a wall of rainforest. Up the road another grand extravagance was hidden in the forests: the model community which Freeport has aptly baptised Kuala Kencana, River of Gold, together with its distinctive Par 72, eighteen hole championship golf course designed by Masters champion Ben Crenshaw.

Izach Wopari, in training to become Papua’s first golf pro, often sees blue and yellow birds of paradise, gather in the trees around the 12th and 13th holes at either end of the day. After a wet day - and the rainfall here is measured by the metre - the birds are joined by wallabies and tree kangaroos.

From the grounds of the Sheraton Timika a boardwalk runs straight into the rainforest. Giant wings whirred as the great hornbills scattered; cockatoos screeched discordantly; an owl - perhaps - added its deep booming call to the croakings and chirpings. Brick-red and mushroom-white fungi relieved the cathedral gloom. Only the remorseless droning of malarial mosquitoes engendered a sense of menace.

Indonesia reigned supreme amidst the muddy lanes of Timika’s sprawling marketplace, in the rows of three-wheeled becaks. Yet the big-boned, frizzy haired men and women, presiding over pyramids of produce or supporting string bags from their foreheads, spoke eloquently of Melanesia.

Irian Jaya, like Dutch New Guinea before it, has been consigned to the dustbin of history. Just ask Marselus Tekige, the 22-year-old student from the Highlands. "When we are independent", he declared, "I will be able to go to university in Jayapura and then I can study tourism in Australia, before going back to my own village to open a hotel". Did I detect a whiff of that good old cargo cult?

At the dirt-floored Bangkalan Restaurant, Kamoro and Amungme tribesmen conversed over Padang-style curried fish and rice - speaking Indonesian, the only language most Papuans share. The Kamoro are a coastal people who sell fish and tablets of sago, their staple diet, in the market. The Amungme are high country hunters and gatherers who resettled, not always happily, on the fringes of town, since the white men and their machines moved in.

There is another, unmistakeable, presence in Timika. It is Freeport Indonesia, the transnational corporation which mines the world’s largest and most remote deposit of copper and gold, situated just below a receding glacier. Freeport supported Marselus, and many others like him, through secondary school and levies itself one per cent of its revenues (not profits) to fund such projects as a newly-opened district hospital.

The company’s private highway inches up a razor-sharp ridge up towards Tembagapura, Copper Town, and the Jayawijaya Mountains beyond, traversing some of the most difficult terrain on the planet. As biologist and adventurer Tim Flannery relates in his book Throwim Way Leg: "In 1910 the English explorer A. F. R. Wollaston took eighteen months trying to struggle over the route... weary weeks stumbling through the relentless swamp and jungle. He lost many of his companions to beri-beri, malaria and drowning on the way."

Alfred, my Freeport escort, swung the LandCruiser through the checkpoint beyond the Sheraton and onto the gravel road which follows the Aikwa River, drowning under its load of mine wastes. In the first few miles we passed a few wandering ebony-skinned figures, some wearing the archetypical string bag, others carrying bow and arrows. Dense equatorial clouds denied us even a glimpse of the distant icefields.

A frighteningly steep gradient loomed ahead: we had risen above a bank of clouds but the road was so steep that the clouds were tipped sideways. Now the cloud forest began… skeletal trunks, draped with moss. This is one of the wettest forests on earth, its dripping green gloom enlivened by tiny flashes of incongruously bright flower or fruit.

After reaching 2,900 metres we dropped, at last, down into Tembagapura, where ten thousand people live and work within a ravine whose walls are streaked with waterfalls.

Tembagapura wore that slightly unkempt feel of mountain towns off-season, exposed without their snow. American housewives chatted in the coffee shop in the little shopping mall, their mannerisms contrasting with the Javanese women who sat demurely nearby.

Further up the hillside was a single arcade of stalls, a commercial centre for the Indonesian and Papuan workers. Local Amungme tribespeople milled about an impromptu market in which the wares were mainly small green oranges and betel nut.

Beyond the township, switchback bends climbed to the mill site at 2,833 metres. Here, where the road could go no further, Swiss engineers built the world’s longest aerial tramway to reach the mine perched at nearly 4,000 metres elevation. Service Tram No. 1 is grey, cold, industrial... and frightening. I clung to the handrail as we soared above a sheer face of black rock, criss-crossed by waterfalls.

On the tortuous drive back down to the lowlands, the sun at last broke through the clouds. We looked out over the forested gorges and mountains, falling away to a dense green carpet beneath a low ceiling of cloud.