Ullr Fest is a festival honoring the Norse god of winter held every January in Breckenridge, Colorado. Festival-goers wear horned Viking hats and participate in numerous fun events, including a parade, snow sculpting, bonfire, shot ski, ski jumps, ice plunges and more.

The most famous events are ''the world's largest'' Ullr Shot ski, a 21+ event benefiting local Rotary Club, and Ullr Ice Plunge, with costumed participants jumping through an ice hole and later enjoying live music, delicious foods and drinks.