Spectacular scenery along Alaska's remote Dalton Highway

This view from the Dalton Highway shows the 414-mile, largely unpaved "haul road" that parallels the Trans-Alaskan Pipeway between Livengood and Deadhorse, Alaska. KIM MURPHY /Los Angeles Times/MCT

DALTON HIGHWAY, Alaska - Although it was early June, snowflakes were drifting down the unforgiving slopes of the slate-gray canyon. The only way up the Chandalar Shelf was a muddy, washboardlike gravel road with sheer drop-offs on our right. Our driver checked the CB radio. No one was heading down the hill, so at 15 m.p.h., our van crept up the narrow S-curve into a cloud.

A golden plover flew in front of us and posed on a snow-covered rock. We were 4,738 feet up and, had Atigun Pass not been fogged in, the view over the Brooks Range would have been spectacular.

We were driving the Dalton Highway, last frontier of the Last Frontier, on a 414-mile road trip across northern Alaska. Alongside it is the Trans-Alaska Pipeline, a major feat of engineering that was built in just over three years, from 1974 to 1977, and that at its prime was pumping two million barrels of oil a day.

In the months before this trip, I had heard of an industrial highway that wound through the top third of the state. People told me of its sweeping mountain ranges, brilliant views of the northern lights, millions of acres of tundra, and caribou herds, all ending at the Arctic Ocean.

Ever hear of the boreal forest that circles the northern third of the globe? This road goes through it.

So I signed up for a tour of one of America's most remote highways. The James B. Dalton Highway is named after an early arctic engineer and referred to as "the Dalton." Many locals call it the Haul Road. It has a reputation for blowing out tires, and for avalanches, steep grades, and speeding trucks that kick up enough gravel to crack your windshield.

I picked the Northern Alaska Tour Co., which was advertising 2½-day trips up the road. The firm would do the driving, put us up for two nights, then fly us back from Deadhorse, a commercial settlement a few miles from the Arctic Ocean.

We met our guide, Robert Weeden, on a cloudy June morning at the company's offices near the Fairbanks airport. It was 56 degrees, the warmest we'd be for the entire trip. Our Ford Escape van was equipped with snacks, bug repellent, a satellite phone, and a CB radio. Six passengers - a couple from Taiwan, two women from New Zealand, a man from Chicago, and me - clambered in to head 73 miles up the Elliott Highway, the feeder road to the Dalton. Within a few miles, we were off the power grid and bereft of any decent Internet connections. Following us the whole way was the pipeline, snaking up and down mountains like a silver ribbon.

Building it was quite a process. The Trans-Alaska Pipeline System was approved in 1968, and it took several years to settle American Indian land claims and get the necessary permits to build a road through 40 million acres of wilderness. Before the 800-mile pipeline could be built over three mountain ranges and about 30 rivers and streams, a road had to be cleared to get workers, heavy equipment, and supplies to the North Slope oil fields. They couldn't be boated in, and flying in was too dangerous and expensive. They had to be trucked in.

And that is how this massive route over the Yukon, one of the country's largest and most remote rivers, came to be.

Seventeen billion barrels of oil and 41 years later, the industrial supply route has turned into an artery for thousands of tourists, researchers, wildlife biologists, trekkers, artists, and hunters.

There are no ATMs, hospitals, banks, or grocery stores in this wilderness of taiga, deciduous forest, and muskegs. The pipeline, 10 feet above the ground, was designed to last 30 years. It has lasted almost 40. Oil companies have agreed to remove the pipe when oil runs out, but the Haul Road will stay put.

We drove over the only bridge in the United States that spans the Yukon, the third-largest river on the continent, but one that most people never see.

We saw bluebells, cottony willow plants, white-flowered Labrador tea, mountain avens, and blue forget-me-nots. Farther down the road, we found equally varied botany: dwarf willows, crowberry plants, and alpine bearberry shrubs that would turn crimson in two months. Spring, summer, and fall are compressed here. Tons of blueberries appear in July, but by mid-August, the light is fading, and the first frosts start to hit. During the rest of the year, the foxes, voles, and ptarmigan that survive here endure several feet of snow, minus-80 temperatures, and hurricane-force winds.

As do the truckers. They flew by in a cloud of gravel, and Weeden always pulled over so they would not have to slow down. The rules of the road are that the truckers' needs come first, as they haul everything - food, pipes, chemicals, boats - to the oil camps, then haul the trash back to Fairbanks.

For such an isolated piece of real estate, there were a fair number of public restrooms along the way, plus exhibits explaining the wildlife, botany, and history of the pipeline.

We pulled up to the official marker for the Arctic Circle, the point at 66.33 degrees latitude where the sun stays above the horizon the whole day during the summer solstice (June 21) and stays below the horizon on the winter solstice (Dec. 21).

Just before 7 p.m., we entered gentle U-shaped emerald and brown valleys formed by glaciers. These were once the bottoms of ancient oceans. We began to climb. The peaks swept up in graceful waves, and the early-evening sun glinted on far-off peaks. We were at 67.15 degrees latitude three weeks before the solstice, so it was quite light out. We pulled into Coldfoot, population 10, so named because the gold miners who showed up a century ago got cold feet at the thought of wintering there. Our lodgings were old pipeline-construction housing at a spot at Milepost 175 called the Coldfoot Camp. Its two drab corridors included a laundry room, TV room, and a place to leave muddy shoes at the entrance. The bathroom and shower were down the hall. At the no-frills Trucker's Cafe across the driveway, a large bowl of chili was only $4.95.

After dinner, we all crowded into the modern visitor center across the street to hear a presentation from a local ranger.

"Life is hanging on the edge here," Heidi Schoppenhorst told us. "The climate is changing. The last few years, we've gotten a lot of precipitation in June, which causes things to grow more. It's making a big difference to have less snow here."

The next day, we followed the Dietrich River and climbed up the Chandalar Shelf, a 10-percent incline up a cliff. From there, we headed over Atigun Pass and across a plateau, halting at Galbraith Lake for lunch. At this point of the Dalton, the eastern edges of Gates of the Arctic National Park are only a few miles from the western edge of the Alaska National Wildlife Refuge.

We next headed through the tundra. When we walked around, it was like treading on sponges. The North Slope, which undulated in graceful green and brown curves to the north, took us six hours to cross.

Around us was wetland 8 to 10 inches deep, and underneath that, permafrost, some of it 2,000 feet thick. We could see loons, Canada geese, and caribou. As the Franklin Bluffs - slate-gray hills with snowy peaks - came into view, Weeden told us the history of Sir John Franklin's ill-fated 1845 Northwest Passage expedition.

Then, 20 miles out of Deadhorse, at Milepost 394, seagulls appeared in the marsh, and my iPhone buzzed. For the first time since Fairbanks, there was Internet connection.

We pulled into our lodgings at Deadhorse, a two-story building known as Deadhorse Camp that looks like a large container. After we threw our bags into our rooms, we met in a small canteen serving meat-and-potatoes dishes, with few fruits and vegetables in sight. Here, "you take what you get," the cook told us.

On our final day, we jumped into a shuttle van for a trip to the Arctic coast in closed-off Prudhoe Bay.

The guide mentioned that grizzlies and polar bears show up in town in April and at the end of August. During our time there, we saw swans and king eider ducks, sandhill cranes, sandpipers, pin-tailed ducks, spectacled eider, and gulls everywhere. In July, thousands of caribou wander through town. We posed for group pictures, then headed for the tiny airport and a nine-seater that took two hours to fly us over the tundra and jagged peaks and past the undulating hills back to Fairbanks.