If you’re not familiar with the concept of uphill skiing, it probably sounds at the very least like an oxymoron, or at most, pure torture—the kind of thing you do to haphazardly recover from a sloppy tumble down the slopes.

For die-hard skiers, though, “uphilling”—also called “skinning” or “ski touring”—is the best way to access a mountain’s most pristine terrain.

The concept is simple: Use specialized equipment (sticky coverings for the bottom of their skis; special bindings that release from the heel, like telemarking boots) to skip the chair lift and hike up to the top of a run instead. Ski down. Repeat. How much you hike is up to you.

Unlike telemark skiers, the goal is to traverse uphill—and occasionally across ridges, cross country style. Compared to traditional backwoods skiing, it's a bit more intrepid. This isn't just about shuushing through the glades.

For some, uphilling can mean climbing an additional 30 feet from the top of the highest lift for a few moments of unobstructed skiing (and bonus bragging rights). For others, it means an exhilarating way to access backcountry areas that aren’t serviced by lifts at all—to a monastery in the Swiss Alps, perhaps, or to summits that jut out from Norwegian fjords.

Regardless of where you fall on that spectrum—if you fall on it at all—expect to see more skinners on the slopes this season. The trend is taking over Colorado, with resorts from Aspen to Crested Butte adding it to their official lineups. It’s also booming in Europe, where you’ll find new uphill skiing programs in Switzerland, the Dolomites, and beyond.

Dan Sherman, vice president of marketing at Ski.com, said the rising trend can be attributed to gear improvements that make ski touring less onerous.

“Uphill skiing has long been part of European ski culture,” he said. “But as gear is becoming more versatile and accessible, we’re seeing more and more vacation-goers taking an interest in North America.”

Some resorts will lend their guests specialized skins to attach to the bottom of their skis for an easy taste of the sport; others have special boots and poles available for rent. Companies such as Dynafit and Tecnica are increasingly producing "tech bindings" and boots that let skiers use the same equipment for ascents and descents, regardless of skiing intensity. Even snowboarders can get in on the fun—some boards these days split into two pieces that look like short skis, perfect for hiking up slopes.

By Sherman's latest count, 70 mountains in North America have published uphill skiing policies, and the resorts he works with are noticing significant upticks in uphill activity. According to Snowsports Industries America, the reported sales of uphill-style equipment increased by more than 200 percent last winter.