Groomed cross-country trails cry out for snow bikes, but respect the skiers. Photo courtesy of Bike Hugger.

When winter hits, forget skinny tires and spandex; hop on a snow-hungry fat bike. These plus-sized models are the perfect way to keep cranking all winter. Nothing breaks a mountain biker’s heart like the first heavy snowfall of a new ski season. Though most bike trails will recover, temporarily, from that first snow, the inevitability of hanging up spandex bibs for the season looms over every ride thereafter.

For diehards, snow outside means tedious hours inside on mounted trainers and unfulfilling sessions with the infinite Sportscenter loop playing overhead. But to a tiny cult, the first snowfall marks the start of a new biking season—one that hybridizes cross-country skiing and mountain biking.

Indoor pedalling is beneath fat bikers, who instead mount steeds so buoyant that only the softest and deepest snow (and the Forest Service) can keep them from riding all winter long. To accommodate the four- and five-inch tires necessary to power their packed-snow prowess, a fat bike chassis is modified with an ultra-wide fork and rear triangle. Despite the increased float provided by the tires’ massive footprint, anyone drawn by the promise of winter rides should know the sport’s limitations and best practices if they want to avoid getting stranded in waist-deep powder (avoidable) or berated by irate skateskiers (mostly unavoidable).

First, stick to well-trafficked trails, particularly of the Nordic variety. Snowmobile tracks are also a safe bet. On either, be sure to hug the trail edge to maintain the groom or hardpack for crosscountry users. Consideration goes a long way. Even with balloon-tired fat bikes, breaking your own trail is tough work, and nearly impossible in six or more inches of snow. Rely on snowshoers, skiers and snowmobilers to pack the trail down, then ride early in the morning or on cold days to reduce your impact on the track. If you consistently adhere to these measures, you’ll be met with gratitude in any of the classic areas recommended below.

Round Valley

With more than 25 kilometers of gloriously corded track near Park City, Round Valley is the premier destination for XC skiing, snowshoeing, jogging, sled dog racing, fatbiking and just about anything else you can imagine doing in the wintertime. Linking up with a number of other nearby tracks, the area is a conglomerate of roughly 80 kilometers of multi-use trails, so many fatbikers find themselves haunting this Nordic system exclusively.

Round Valley can accommodate all biking skill levels, but favors novice riders with its well-maintained trails and gentle topography. The only noteworthy run for advanced riders is Barrel Roll, a trail connecting two intermediate strips of terrain in the heart of Round Valley. This a rea is the gathering place for Park City's many enthusiasts, but the classic trails and perfect corduroy are well worth the crowds.

Bloated tires, a beefy frame and the heart of a polar bear extends biking season through winter. Photo by Peter Redin.

Butterfield Canyon

This Oquirrh Mountain gem may lack technical terrain-the snowmobile track you follow is wide, making it perfect for beginners—but it makes up for that inadequacy with a relentless hill climb. The trail begins at the entrance gate and proceeds uphill to Butterfield Pass. If the trail has seen enough traffic, bikers can also ride the 3.5-mile White Pine Loop, or reach the summit overlook with a 1.5-mile ascent from the pass. Reaching the summit is worth the effort, as riders are rewarded for their labors with an impressive view of Kennecott Copper Mine.

The climb up Butterfield is strenuous, so you may be tempted to stash layers in your car rather than a backpack, but bombing back down the canyon will require every layer you own and a few more you wish you did. Horses are allowed on the trails here, so be aware of both the animals themselves and the post holes their hooves leave behind.

Corner Canyon

Corner Canyon has the highest potential for unadulterated fun, but it often lacks the trail-breaking traffic necessary to make fatbiking feasible. On cool days following a snowstorm, however, advanced riders can indulge in challenging corners, narrow trails, high top speeds, and the occasional tumble into a snowbank.

Although popular trails like Clark's and Ann's may sometimes close due to weather conditions, whenever there's enough hard pack to merit pulling out your fat bike, then most of Corner Canyon's protected wilderness should be open and accessible. Only expert riders are encouraged to tackle the canyon's most difficult trails, which are formidable during ideal conditions, but downright terrifying for fat-bike novices.

American Fork Canyon

The snowmobile trails deep inside of American Fork Canyon give ambitious snow bikers access to classic challenges like Granite Flats, Silver Lake Flats, and the unparalleled Tibbie Fork Trail. The trails here bisect the limestone bulk of Timpanogos and Lone Peak's granite spire, so every vista is worthy of John Muir's prose. Regardless of your trail choice, the technical climbs that spider above Tibbie Fork Reservoir into Pine Hollow will culminate in spectacular views of the Wasatch backcountry, but only after strenuous gains in elevation.

These gains are countered by an epic descent that generates blazing-fast speeds and frig id core temperatures, so match your insulation layers to the reality of a mountaintop wilderness. The majority of routes in this area are intermediate to advanced, so wh ile a novice may feel overmatched by the tight singletrack, an experienced fat biker should feel right at home.

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