Rigby Lake RUMBLE KIDS Triathlon 2026

The Rigby Lake RUMBLE is a multi-sport race held at Jefferson County Lake in Rigby, Idaho. It features calm lake swimming and very flat bike and run courses. Produced by Tri Peaks Epic Events, it offers several participation options: Sprint and Olympic triathlon, Sprint and Olympic duathlon, a 5K run, a 10K run, and a two-person Sprint Team option. The sprint triathlon is suitable for first-time participants, while the Olympic triathlon provides experienced athletes with a fast course that has minimal climbing. The duathlons maintain the run-bike-run format for those who prefer to bypass the swim. The course begins with clear, calm water in the lake, followed by flat roads for the cycling and running segments. Participants frequently highlight the helpful volunteers, supportive organizers, positive race-day atmosphere, and a course that feels manageable for a first triathlon. Categories are available for families, walkers, new racers, club athletes, and competitive triathletes. The event was previously known as the Rigby Lake Rumble Triathlon but has expanded to encompass a wider local multi-sport event. A unique tradition is the Rumble Slide, where athletes can slide out of the swim area to receive a bonus merchandise item.