Emily Schwing

The plummeting mercury in Alaska this time of year doesn't keep bikers inside. More and more of them are heading to recreational trails and to the office on "fat bikes." They look like mountain bikes on steroids, with tires wider than most people's arms.

Kevin Breitenbach runs the bike shop at Beaver Sports in Alaska's second-largest city. Aboard a fat bike, he makes his way down a trail that winds through a forest as wet, quarter-sized snowflakes drop from the sky. Visibility is low, and the snow hides the roughest spots on the trail.