The 28 Below Fatbike race is a 50k lolly-pop loop with around 2,800 ft of climbing. It is the only race in the Black Hills that is permitted to take place on groomed snowmobile trail. Although the race takes place in mid March, the snow conditions tend to hold in the high country of the hills.

The 50k lollypop loop starts and finishes at Spearfish Canyon Lodge, and follows the groomed snowmobile trails that are permitted by the USFS. Race day is the only day of the year that riders are permitted on the groomed snowmobile trail here.