Grand Slam of Ultrarunning Series

Grand Slam of Ultrarunning Series is listed as a 100-mile trail run in Kaysville, Utah, on September 11, 2026. The name refers to the Grand Slam of Ultrarunning, a challenge earned by finishing a set of 100-mile races within a single summer, and this September date in Kaysville corresponds to the final 100-mile leg of that series.

This is not a race for a first ultra: the runners chasing the Slam arrive with several 100-milers already in their legs from the same season. If you are working toward this kind of goal, the training question becomes recovery as much as fitness, since you have to absorb one 100-mile effort and start another a few weeks later. Plan a long-term program that alternates race blocks with genuine rest, practice night running and fueling over 24 hours or more, and treat pacing as the difference between a finish and a DNF.