Next services: 244 miles: Armed with permit, insect repellent, CB radio and the collected works of Tater Bob, Bill Pannifer follows the Alaska pipeline to the Arctic Ocean

We are driving out to the coast. Not the East Coast, nor the West Coast, but the North Coast: the northernmost point in the United States accessible by vehicle. Our route is on all the maps, a dead straight, lonely-looking line up from Fairbanks to the shores of the Arctic Ocean. We've already driven three thousand miles from San Francisco, and we're not going to stop now, just because it says 'Restricted Road'.

We're heading for the Dalton Highway, built in 1974 to service the Alaska pipeline on its final 500-mile stretch up to the oilfields of Prudhoe Bay. Also known as the North Slope Haul Road, it's a slippery, gravelly, two-day trip through some of America's most spectacular wilderness. Most of it, in theory at least, is off-limits to the public, the necessary permit almost impossible to obtain.

But in Fairbanks, Clark Milne of the Department of Transportation is eager to oblige. As a writer, I am deemed to have the necessary 'commercial' purpose for driving the route. I sign an unnerving form, in duplicate, absolving the state from responsibility for my rescue, waiving possible claims for injuries or damages, and agreeing to carry two spare tyres, a spare headlight, flares, tools, snow chains, insect repellent, a CB radio, and emergency food and medical supplies. I'm warned not to feed bears, nor wolves, and not to expect any help from the pipeline operatives as they have better things to do. 'Have a good trip,' beams Mr Milne.

We soon discover that the Dalton wasn't built for vehicles such as our modest Ford van. It was built for trucks, and for trucker- poets such as Tater Bob, who celebrates it in a slim volume, The Road Leads North, obtainable from local stores. After 10 years of plying the route, Tater has become its laureate, the McGonagall of the North Slope:

Oh Lord, please,

I hope my truck doesn't fail

Cause I've got to go North

Up the Prudhoe Bay Trail.

Tater and his ilk drive huge, 18-wheel Mack trucks with oversized loads at breakneck speed up and down the narrow road, sending clouds of dust and fist-sized chunks of rock flying into unfortunate windscreens. The trucks view this as their domain, and we've heard tales of CB-co-ordinated conspiracies to crush disrespectful car drivers. Just tales: but we still pull right over every time a truck goes by. It's hairiest at night, on the narrow parts, when the big brutes seem to come within an inch of sideswiping us.

The road is a strip of gravel several feet deep, sprayed with oil, and with an underlay of plastic foam to prevent the permafrost thawing beneath it. It can be tolerably smooth or a road from hell, depending on weather conditions and maintenance. We rattle along at 45 or so, green and gold Boreal forest at first, willow, birch and aspen gradually giving way to stunted black spruce and the swampy undergrowth known as muskeg. The colours have slowly deepened as we've come up through Canada, a journey into autumn rivalling anything in the eastern states.

Zigzagging through it all is the pipeline. The Japanese-made, 48in-diameter tube stretches from Prudhoe down to the ice-free port of Valdez (Val-deez, as in Exxon Valdez). It's uncompromising but not ugly: more a series of enigmatic contrasts with forest and tundra. The locals love the thing. It accounts for 25 per cent of US oil production and means each Alaskan receives an annual dividend of dollars 1,000 (about pounds 700) from the oil companies instead of paying state tax. People drive to observation points to watch it glinting lucratively in the Arctic light.

The trip takes two full days of driving, each way. Four days of contemplation punctuated by bracing moments of fright. And the odd memorial to the less lucky:

Chuckie's last ride is marked with a cross,

It was the Lord's gain but certainly our loss.

The Lord is much in evidence around these parts, not just in the scenery but in a certain idiosyncratic frontier spirit. Seventy miles out of Fairbanks, for instance, in a cluster of log cabins, the Carlson family runs the enterprise known as Joy, Alaska: a general store, fox farm and orphanage for an adopted brood of up to 19 difficult kids from around the world.

The Carlsons loaded their school bus and drove up from Minneapolis not in search of oil money but out of conviction: alone among states, Alaska lets them educate their flock at home. The robustly biblical curriculum includes biology (helping Dad eviscerate the occasional caribou) and, by the looks of it, tourist marketing: even the youngest children produce a news sheet about the place, on sale for 50 cents, and the store has religious texts, souvenirs, canned food and a special offer on foxes' heads: dollars 1.50 each.

While Jade (16, from India) fills our thermos, and younger ones rush about with bows and arrows, Joe Carlson disabuses me of any pioneer notions of my own. He's already met one Brit on the Dalton this year. On a bicycle. En route to Argentina. He also explains why most of the highway remains off-limits to the public: the state wants to open it so it will qualify for federal highway funding, but faces legal opposition from North Slope native interests that fear subsistence hunting rights will be jeopardised.

The oil companies don't want responsibility for dealing with convoys of motor caravans and there's also the problem of what folks up here call 'daisy sniffers' - environmentalists. Protecting the North Slope's wilderness status is a highly charged issue, and not limited to who uses the road.

We follow the pipeline across the Yukon, and soon spot our first moose, grazing nonchalantly by the highway. The locals warn that a slow-moving van often means illegal hunters taking potshots at the wildlife. But nobody seems to have warned the moose, which stares at us obtusely and proceeds on its way. Animals are impossible to avoid: 'road kills' are frequent. We see deer, caribou, arctic fox and a fast, feral flurry we convince ourselves is lupine. Hawks and ravens soar overhead, but the bears are avoiding us.

Until this year, only a functional little sign marked the Arctic Circle, at latitude 66 degrees 32 minutes. Now it has a snazzy little podium and observation point, first fruit of a detailed tourist development plan, to be extended northwards if local objections are overruled. Lots of people drive this far just to cross the Circle and return: we watch a couple of teenagers arrive, undress, and photograph themselves naked in front of the sign. It's already a bit nippy for this kind of northern exposure. In winter it can drop to minus 80F.

Wiseman, up the road, sells itself as 'historic', but the picturesque, antler-capped cabins harbour real people with real get-out- of-town stares. The place has gone to the dogs: 28 human inhabitants are outnumbered by the huskies Joe Henderson breeds for sled dog mushing. Occasionally they turn up in the movies: Disney's White Fang featured Joe's animals. But there's nothing of the theme park about the town or the trading post Joe runs with his wife, Sherry. Part of the store may be a museum, but past and present blur into one here. There's a rack of guns on the wall, and recruitment ads for the National Rifle Association, while outside, bloody animal hides dry on racks.

At Disaster Creek the road ends for the general public. But at the checkpoint the expected State Trooper is nowhere to be seen, and, Joe tells us, no one has been turned back all season. In effect, anyone can travel this road, without permits or equipment checks - anyone unfazed by a sign saying 'Next services: 244 miles'.

Now we're past the last stunted little tree and into the tundra, in shades of orange and red, before us a spectacular panorama of mountains: the Brooks Range, the northernmost section of the Rockies, still largely unnamed and unexplored. The vertiginous up- and-down sections, with nicknames such as Rollercoaster and Beaver Slide, give way to protracted ascents. Our trusty V12 groans up the lengthy 10 per cent gradient of the Chandalar Shelf.

Soon we're crawling through the Atigun Pass, Alaska's highest road pass, where it is forbidden to stop because of avalanches. Our first snow is swirling about us on the icy road through the clouds. Then down again, slowly, to the final hundred miles of level, almost featureless tundra; off to our right, 19 million acres of protected territory known as the Arctic National Wildlife Refuge (ANWR).

We realise we haven't met any traffic for hours. So we walk out on to the tundra to savour the loneliness. When we come across our next truck, it's on its side in a ditch, victim of the previous week's flooding. When it rains, the Dalton is more river than road.

Lloyd counted his blessings when he went over the bank,

It totalled his truck and tore up his tank.

The rocks and potholes get worse: it's a boneshaking ride and we pray for the suspension. They lay the gravel more deeply here to prevent frost heaves, but it seems to take the form of big, rocky chunks, and we shudder along at less than 20mph. Now we're at sea level except for pingos, little hills of solid ice rising out of the permafrost. Tundra becomes arctic swamp and we drift into Prudhoe in a cloud of mist. It's an eerie experience, sloshing through grit and mud in the freezing fog with the occasional headlight drifting towards us out of nowhere.

The terminal itself is terminally bleak, a grey, muddy jumble of stacked Portakabins and machinery. When, at the end of Five Easy Pieces, Jack Nicholson dumps his girlfriend and hitches to Alaska, I imagine him ending up here, the ultimate zone of self-exile. Prudhoe's population is 95 per cent male. There's a complete ban on alcohol and workers endure a 12- hour day, seven days a week for an average six-week stay: anyone staying longer is given a compulsory psychiatric check-up.

Employees stay either in reportedly luxurious company quarters or in hotels such as ours, the North Star, with separate wings for day and night sleepers. Our dollars 150 buys a tiny room and unlimited access to the cafeteria, where taciturn oilmen over-eat in an atmosphere of calming neutrality. Out on the tundra patches of marsh and puddle are named after sweethearts back home: Lake Sally, Lake Michelle, Lake Janet.

To travel the last few miles to the ocean, on security-controlled company roads, we must take a tour. Our guide, Nina, is part Athabascan Indian, working her way through teacher-training college. She saves a lot; but then, there's not much to spend money on.

The tour has a recurring theme. Arco and BP are trying to outsniff the daisy sniffers. The buildings are on stilts so that they can be removed without damaging the tundra, and are drab, unobtrusive green, the colour of duck eggs, so as not to disturb the wildfowl. Signs everywhere warn that caribou have legal right of way, and a vast gravel pit, we are told, is to be expensively restored to its virgin state when the oil runs out . . .

Chilling words those, chillier than the Arctic winds to most Alaskans, with 85 per cent of their income oil-dependent and with ominous talks about taxation in the state Senate. What's needed is another oilfield.

As a condition of access for her tour, Nina has to screen a video and hand out brochures: 'Open ANWR - America's Energy Future'. A small coastal section of the wildlife refuge has been earmarked as the second Prudhoe Bay. Nina seems uneasy as she runs the tape: it's Athabascan land. We're being fed propaganda: a Sellafield tour at dollars 60 a throw. Eventually Nina drives us to a gravel jetty reaching out into the Arctic Ocean. If I take a dip, I qualify for the Polar Bear Club and a special badge. But I content myself with staring into the grey water, soon to be iced over for eight months.

I have mixed feelings about ANWR and about the road. Some of the greenwash rings true: development of the tiny area concerned would probably be circumspect. Many Alaskans resent paying the economic price to assuage the environmental conscience of the 'lower 48' - those below the 48th parallel. Yet there are potent arguments for keeping some of the last virgin wilderness in the world off-limits.

Whatever happens, the highway itself will inevitably be upgraded and tamed for the motor caravans, the worst bends ironed out, more and better services installed. There will be trailheads and visitor centres and campgrounds. But as I stand in the freezing wind at Mile Zero of the pipeline, I'm glad we've seen this unique blend of remote beauty and weird technology, while it remains a bit intractable, a bit risky. Tater Bob's doggerel hits home:

The Lord did good when he created this land,

It is the last frontier to be touched by man.

Getting there United Airlines (0800 888555 has a 21-day Apex fare to Anchorage via Seattle for pounds 589 April-June and September, pounds 689 July-August. Most air passes do not include Alaska.

Roads For the up-to-date official position contact the Department of Transportation, 2301 Peger Road, Fairbanks AK 99701; 0101-907 451 2209.

Accommodation and services Coldfoot Services, 174 miles in, offers doubles for dollars 115 ( pounds 80). The North Star Hotel, Deadhorse (Prudhoe Bay) has doubles with food for dollars 150 ( pounds 105). Tow charges in the event of breakdown are dollars 5 per mile.

Reading The Milepost is an essential, meticulously detailed guide to road travel in Alaska and north-west Canada. From Discovery Publications, 22026 20th Ave SE, Bothell, WA 98021; 0101-206 487 6100. For a general guide, take Let's Go: Pacific Northwest, Western Canada and Alaska. The Road Leads North, by Tater Bob, from Deadhorse General Store, dollars 2.

(Photograph omitted)