Dizzy Horse Backyard Ultra

Event overview

Dizzy Horse is a winter backyard ultra held in Idaho Falls, Idaho on December 12, 2025. The event is hosted at the Bonneville County Exhibition Hall and Sandy Downs Park. The format requires each remaining participant to complete a loop of 4.167 miles every hour; the race continues until only one participant completes one more loop than the next finisher. Basic registration is listed at $50, with optional paid upgrades such as a deluxe aid station, reserved indoor 10'x10' transition spaces, hoodies, and T-shirts.

Course, format and logistics

The loop mixes desert, grass, horse racetrack, dirt, sand and a short section of asphalt or snow. The organizer describes about 25% grass, 20% racetrack, 35% dirt, 8% sand and 12% pavement. Elevation gain is roughly 40 to 80 feet per lap, with one sand section giving about 35 feet of climb. Water is available at the 2 mile mark. Competitors must start each lap at the top of the hour and remain on course until the lap is completed. Crew may not assist runners while they are on the loop but may offer aid after a runner crosses the finish line for that lap. A general indoor transition area is provided; a limited number of reserved heated 10'x10' spaces are available as an upgrade. Results are based on completed loops; benchmarks and DNF awards are given for set distances. Visit the organization's website for the most recent information.