Chama New Mexico USA - Thick black smoke billows from the engine, flooding the air with a pungent cloud of ash and soot.
 
Wheels clack against rails.
 
Cars lurch from side to side.
 
Ahead, the coal-fired locomotive hammers and hisses as it slowly muscles its way up the four percent incline toward Windy Point.
 
"I-think-I-can, I-think-I-can, I-think-I-can," my observant wife, Dianne, whispers.
 
The pulsing throb from the 90-year-old steam engine perfectly mimics "The Little Engine that Could."
 
We're on board the Cumbres & Toltec Scenic Railroad, whose tracks connect Chama with Antonito.
 
Stretching 64 miles in length and topping 10,000 feet, it's America's loftiest and longest remaining narrow gauge rail route.
 
There are six optional ways to take the train.
 
Passengers can park in either Chama or Antonito, ride a chartered morning bus to the opposite end and take the train back.
 
Or they can take the train to the opposite terminal and ride an afternoon bus back.
 
A final option is to simply ride the rails halfway from either side, swap trains midway and return to the starting depot after lunch.
 
We opt for the steeper eastbound train-up, bus-back option, and book a rail-themed room at the Gandy Dancer B&B in Chama.
 
With its whistle blowing, the seven-car train slowly chugs up the tracks.
 
Folks wave from campgrounds and rail crossings, their cameras clicking faster than paparazzi chasing the royal family.
 
Like Prince William and Kate, we wave back.
 
Tracks cross the Chama River and head into an aspen and conifer forest interspersed with hillside meadows and verdant valleys.
 
Come autumn, this mountain route promises to glimmer with more gold than Fort Knox.
 
Fellow passengers shout excitedly at the first deer sighting.
 
Yesterday, folks saw a bear.
 
A small sign marks the Colorado state line.
 
Before trip's end, we will make 11 border crossings.
 
Two and a half tons of coal and 4,000 gallons of water later, the train reaches its high point atop 10,015 foot Cumbres Pass.
 
"The highway department has it listed as 10,022 feet," the parlor car attendant says, "but we use 10,015 because that's what the railroad originally had it listed as."
 
After filling the locomotive's water tender from a spring-fed tank, we cross the highway one last time and wrap around Tanglefoot Curve.
 
From here to Antonito, we'll be traversing wildlands penetrated only by the tracks.
 
The train stops for lunch at Osier.
 
This was once a small community complete with store, rooming house, and depot.
 
Today, it sports the railway's cafeteria, where passengers devour complimentary meals.
 
Our eastbound train arrives first, followed by the westbound train about 15 minutes later.
 
The crews and passengers electing the half-way option will swap trains for the return home.
 
We continue on, soon re-entering New Mexico.
 
After passing a monument to President James Garfield, we reach the plunging edge of Toltec Gorge.
 
The train slows to a mere crawl as tracks hug the lip of the 800 foot wide, 600 foot deep defile.
 
So steep is the precipice, signs warn passengers not to throw rocks for fear of bonking fishermen below.
 
It's good I'm not acrophobic.
 
We pass through a pair of tunnels, one blasted through solid rock, and another timber-lined through softer soil.
 
Not far beyond, tracks leave the forest and enter the sage-clad realm of the San Luis Valley.
 
It's all downhill from here.
 
"I-thought-I-could, I-thought-I-could, I-thought-I-could," our proud steam engine murmurs once again.
 
Dan Leeth.