It’s one degree Fahrenheit. The air bites at your skin as the sun drags in the morning sky. There’s a foot of snow on the trails. And you’re about to go ride.

Fat biking is said to have dual beginnings: one in the desert and one in the snow. It’s believable, because these monster trucks of mountain biking are as equally at home on dunes of sand as they are in drifts of powder.

“When I was a kid, I loved to go out and play in the snow,” said Joey Ernst, owner of Velorution Cycles and Bedrock Bags in Durango. “That part of me just never really grew up.”

Velorution just may be the only shop of its kind in the existence, a full service bike shop/bag manufacturer, Ernst’s partner, Andrew Wracher, hand makes ultra burly bags specifically for bike touring and bike packing.

After chasing Ernst around the snow-laden trails, it’s easy to see that kid within, under an icy beard and stiffened face.

“I’d smile but my face is frozen,” he said after a single-digit outing above Durango. “But it’s really fun to go out and get fresh tracks on a powder day. That’s not something you can do on bicycles. I don’t ski, so this is the way I get out in the winter time.”

With rosy, rigid cheeks, Sandhya Tillotson called it playful, despite the temps.

“It’s fricking cold,” she said. “But at least the sun is coming out.”

She said she likes venturing off trail. Both Ernst and Tillotson are avid adventure cyclists, touring broad landscapes in all conditions. When these two go for a ride untethered by a media crew, they’re not coming back for a while.

“It’s such an unexpected joy,” she said. “It opens up so many possibilities and new places that you can’t even ride in the summer.”