The format
Backyard Ultra Rules: How the Format Works
One loop every hour, on the hour. Here are the standard Backyard Ultra rules, how a winner is decided, and what to check with your race organiser.
The Backyard Ultra format is easy to explain—and hard to leave. Here’s how the standard rules work, from the first bell to the final yard.
The format: one yard every hour
A Backyard Ultra is an endurance race built around a simple, repeating schedule. Runners start a new loop every hour, on the hour, and keep going until only one runner completes a loop that nobody else finishes.
There is no set total distance and, in an open-ended Backyard Ultra, no fixed finish time. The objective is to complete more yards than the other competitors. You do not win by being the fastest over a fixed course; you win by being the last runner able to complete another yard alone.
Every yard starts on the hour. The race has no predetermined final distance.
How long is one yard?
Under the standard rules published by Big’s Backyard Ultra, one yard is 4 miles and 880 feet, or 6.7056 kilometres. The distance is set so that 24 yards add up to 100 miles (about 160.9 kilometres).
The course can be a loop or an out-and-back route. The exact terrain, surface, elevation and conditions depend on the event. A technical trail or a hilly course may take considerably longer than a flat route, even when both cover the same distance.
The start is on the hour
Every yard starts exactly one hour after the previous one. Organisers give warnings three, two and one minute before the bell. At the start bell, competitors must be inside the starting corral and ready to go.
A late start is not allowed under the standard rules. If you are not in the corral when the bell sounds, you cannot start that yard. Use the warning signals to wrap up food, kit changes and other tasks in time.
The next yard starts at the bell. There is no late-start window.
Finish each yard in less than an hour
A yard must be completed in less than one hour to count. Finish early and the remaining time is yours to recover and prepare before the next start. You might use it to sit down, change clothing, eat, drink, or organise what you need for the next loop.
The time between yards is part of the format. A faster loop gives you a longer break, but the fastest pace is not automatically the best one to repeat for many hours. The challenge is finding a rhythm you can sustain while leaving enough time to reset at the start area.
Rules while you are on the course
The standard rules also set boundaries for what can happen during a yard. Competitors must stay on the course until they complete it, except for restroom breaks. Personal aid is not allowed during a yard, and non-competitors—including runners who have already stopped—may not accompany active entrants on the course.
Artificial aids, including trekking poles, are not allowed under the standard rules. Slower runners must allow faster runners to pass. These rules help keep the competition consistent, but your organiser’s event briefing should explain how they apply on the specific course.
Crew support happens between yards; personal aid is not allowed during a yard under the standard rules.
How an open-ended Backyard Ultra ends
The race continues until one runner completes a yard that no other competitor completes. For example, if several runners finish yard 20 but only one completes yard 21, that runner is the winner. The other runners are credited with the yards they completed.
Under the standard rules, all competitors other than the winner are technically recorded as DNF (“Did Not Finish”), even if they complete a substantial distance. If no runner completes one more yard than the others—for example, if all remaining runners stop or fail to finish the same yard—there is no winner.
What is a Backyard 24?
Some events use the Backyard format for a fixed duration. These may be called a Backyard 6, Backyard 12 or Backyard 24, according to the number of hours. A Backyard 24 ends after 24 hours rather than continuing until one runner remains.
Under the standard Backyard 24 rules, no winner is named. Participants either finish the event or are recorded as DNF, and the other Backyard rules still apply. Check your event details so you know whether you have entered an open-ended Backyard Ultra or a fixed-duration variation.
Check your event’s rules
The rules in this guide are based on the standard format published by Big’s Backyard Ultra. Individual races may have additional requirements or local procedures, such as mandatory equipment, course instructions, or how results are presented. Read the runner information from your race organiser and ask them if anything is unclear.
Once you understand the rules, you can start planning the routine between yards: how you will pace, recover, eat, drink and get ready for the next bell. Practising that routine in training can make race day feel more familiar.