The Alaska Railroad train slows to a crawl as the passengers shift their eyes from the rocky crags of the Alaskan Range outside one window to peer out the opposite side toward a stand of black spruce to the south.
Rising from the permafrost forest is an old trapper's cabin with shrubs and trees sprouting from its roof.
The Alaska Railroad runs daily between Anchorage and Fairbanks from mid-May through mid-December. In the off-season, it runs from Anchorage to Fairbanks on Saturdays and returns on Sundays.
The trip takes 12 hours, with a handful of stops in the summer, but in winter it is a so-called Flag Stop train, during which the train stops for those who flag it down rail-side.
Summer fares are $165 each way. Passengers can check two bags for free.
To learn more, see www.AlaskaRailroad.com or call 1-800-544-0552.
"Out in the middle of nowhere," passenger Bill Klyn says as his camera whirs. "I wonder what made him decide that's the place for his cabin."
There is no shortage of wonder for those taking in the vistas along a big piece of the country's biggest state by riding the famed rails of the Alaska Railroad during the height of the fall foliage season.
The daily 356-mile trek between the state's two largest cities, Anchorage and Fairbanks, draws close to 800,000 seasonal visitors looking to experience Alaska's backwoods and tundra from the comfort of a rail seat or dining car, with all the wild amenities splayed before them.
From the vast palette of fall colors to glimpses of Dahl sheep and the occasional moose, these snapshots of wild Alaska turn gawking riders into wild shutterbugs.
"The colors are just amazing, and this place is just huge," says Janet Reese, a San Diego chef riding the train Sept. 8 during a personal tour of southern Alaska.
"I love it," Reese says as she snaps images of Healy Canyon. "Alaska's been on my list for a long time. I almost flew out of Fairbanks. I'm glad I was told that the train was a pretty nice way to go."
Spawned in 1904 to link Fairbanks-area gold mines with the rest of the world, the Alaska Railroad runs 470 miles from the coastal hamlet of Seward, through Anchorage and a bevy of small outposts, all the way to Fairbanks.
It began as a private venture by Alaska Central, but the company managed to carve only 71 miles of track into the hardscrabble southwestern part of the state before it went belly-up in 1912.
Two years later, the federal government decided the railroad was vital to the Alaska Territory, so President Woodrow Wilson authorized its construction. The route finally was completed in 1923. The state took ownership of the rails in 1985 and has been running the route ever since.
The single track has occasional pullouts so other trains can pass the two engines and 15 cars that make up the train. The cars skim the corner of Denali National Park and Preserve at an average of 38 to 40 mph, slowing at times to accommodate rubberneckers seeking a view of North America's tallest peak, the 20,320-foot Mount McKinley — also known as Denali.
Just what they view varies daily, says Ken Smith Jr., who the past six years has been the conductor on the line, leading a crew of two engineers and two tour guides who regularly tell visitors what they're seeing — or missing.
Even when the mountains stand hidden in the clouds, the bright yellows of birch fields dazzle the eye. This day's atmosphere offers a common mix of sights.
"The colors are so beautiful," Smith says. "The clouds are higher today than yesterday, for sure."
Smith has seen the peak of Denali — the coup de gras of the adventure — only six or eight times during the 2012 season that opened in mid-May and closes in mid-September.
"For that, this season has been worse than others," Smith says. "When it's clear, it's awesome."
Smith constantly is peppered with questions from riders wondering whether they'll get to photograph Denali today, and what wildlife they're likely to see.
"As far as the animals go, it's a roll of the dice," Smith says.
This time, the dice land on seven as the train slows. Along a nearly vertical slope are the top fauna for railroad visitors. Five Dahl sheep, including one large ram, appear first like white forms on the dark rocks, but close enough for Klyn to capture with his 200 mm lens.
"I got it," says Klyn, a Wyoming man accompanying a small cadre of outdoor writers on a trip from Fairbanks to Anchorage. "I got it, man. I got it."
Cheryl Graeve certainly got it, and much more. The Virginian ripped off 170 photographs between Fairbanks and Denali, roughly one per mile in the first leg of this 12-hour journey.
She and husband Pete Graeve considered flying to Anchorage, but a train ticket costs roughly the same as a flight, and she had this Friday to kill.
"I expected the fall colors but I didn't expect all the mountains and rivers," Graeve says. "It's fantastic."
As the train lumbers through the forest, Graeve and others wonder whether they'll be lucky enough to get the money shot.
Smith squints at the sky. Sinking clouds shroud some of Denali's lesser Alaska Range brethren, and he shakes his head.
"I doubt it today," Smith says.
The train snakes over 215-foot-tall Windy Bridge past milky, glacier-fed rivers and then summits the Continental Divide 158 miles into the trip. After passing through the incongruously named Honolulu, Alaska, the train passes ever closer to the best Denali viewing angles.
Vast sanguine seas of fireweed cloak the landscape between tall stands of spruce and birch, jaw-dropping views interrupted by willow stands and brush.
Out the left window, glacier-carved lakes sport beaver lodges the size of minivans. To the right, snowmelt creeks carve through basalt formations near exposed coal veins.
"It's like 'The Exorcist,' " Klyn declares. "Your head's spinning around, trying to figure out which way to look."
As the train inches over a rather sketchy-looking bridge traversing Hurricane Gulch, all heads are pointed to the north.
If the clouds cooperate, Denali will rise behind the deep gulch like a snow-capped pyramid bathed in JPEG-friendly daylight.
But all anyone sees is a gray curtain rising over the gulch.
No Denali today.
"Yeah, people get a little disappointed when they don't see it, but what are you gonna do?" Smith says.
"I tell them, I can't control the weather or the animals," Smith says. "But I can get you a safe ride to Anchorage."