Bonneville Backyard Ultra
Charleston, United States • 24 Apr 2027
Bonneville Backyard Ultra
The Bonneville Backyard Ultra is a last person standing ultramarathon held in Provo, UT, near the Deer Creek Reservoir. The course is an out and back along the reservoir with about 2.08 miles each way, making a 4.167 mile loop that runners must complete every hour.
Runners must start each loop on time and be inside a painted corral before the bell rings. If a runner fails to start a loop on time they are out of the race. The event does not allow late starts or pacers. Only one runner finishes with a valid completion; all other participants record a DNF.
The terrain is described as mostly smooth and very runnable. The format emphasizes repetition and hourly restarts, which introduce a strong mental component and can cause sleep deprivation over many loops.
Organizers use hourly signals to mark the countdown and the start of each loop: three whistles for three minutes to go, two whistles for two minutes to go, one whistle for one minute to go, and a bell exactly on the hour to begin the next loop.
Organizers may invite a small number of waitlisted runners to be present on race day as standby participants; these standby invitations are not guaranteed entries. Visit the organization's website for the most recent information.