Endless Day Backyard Ultra

OCT
17
2026
A backyard ultra in Richfield, UT where runners start a 6.55 mile loop every 90 minutes and continue up to 24 hours. Multiple distance milestones are available from 10K to about 100 miles.
Sat 17 Oct 2026
10k Half Marathon Marathon 50k 50 Miles

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Endless Day Backyard Ultra

The Endless Day Backyard Ultra is a backyard-style ultramarathon held in Richfield, UT, rescheduled to October 17 after poor air quality from local forest fires forced an earlier date change. The event uses a repeating 6.55 mile loop that starts every 90 minutes. Runners must complete each lap within 90 minutes and may continue as long as they can, up to 24 hours.

Distances offered at the event include:

  • 10K
  • Half Marathon
  • Marathon
  • 50K
  • 50 Miles
  • 100ish Miles

Lap milestones convert to standard distances: one lap equals 10K, two laps equal a half marathon, four laps equal a marathon, five laps equal 50K, eight laps equal 50 miles, and about 15 laps equal ~100 miles. The overall winner is the runner who goes the furthest within the time limits; if multiple runners remain on the final lap, the first to finish that lap is the winner.

The course is mostly flat dirt farm roads with three blocks of pavement near the park, and offers views of the Pahvant Range and Red Hills. A full aid station will be at the start and finish park area, another aid station will be about halfway on the loop, and two self-serve coolers will be available. The Nielson Family Park provides room for personal base camps and will have areas roped off near the northern pavilion.

Registration is tiered by intended laps with different prices before and after October 4. Registration closes October 13 at 11:59 PM MT.

Weather in Central Utah in October is unpredictable and can include sun, wind, and snow, so participants should prepare gear and strategies for varying conditions. Visit the organization's website for the most recent information.

100 mi
~100 Miles
50 mi
50 Miles
50 km
50k
Marathon
Marathon
Half Marathon
Half Marathon
10 km
10k
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