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Backyard Ultra in France

The concept
Why 6,706 kilometers ?
Official Infinity Trail Circuit
Why is it accessible to everyone ?

The Infinity Trails Backyard are events of the Backyards Ultra calendar in France.


Created by Lazarus Lake, the organizer of the famous and mythical Barkley in Tennessee, the principle is very simple :

  • The course is a 6.706 km (4 miles 880 feet) loop.
  • There is a departure every hour. You have to do the loop in less than an hour. If you finish it before, you can rest while waiting for the start of the next loop, which is one hour later than the previous one.
  • Example: if you finish the 1st loop in 45 minutes, you have 15 minutes before the next start. If you finish the loop in 58 minutes, you will have only 2 minutes of rest before the next start.
  • The goal is simple: to complete as many loops as possible within the time limit.
  • The winner is the last person to complete a full loop.

Because Laz wanted a loop to be made 24 times ( in 24 hours) so that it makes 100 miles ( 161 km) exactly (mythical distance in the US)

Today, the Infinity Trail circuit includes 5 official events:

  • Infinity Trail – Ile d’Aix: qualifier for the circuit final
  • Infinity Trail – Hossegor : qualifier for the circuit final
  • Infinity Trail – Dijon : qualifier for the circuit final
  • Infinity Trail – Les terrils : qualifier for the circuit final
  • Infinity Trail – Normandy: national final, qualifier for the world final

Even if the numbers can scare you, Backyard ultra are accessible to everyone… Principle is simple : to do 6.7 km in less than 1 hour, so that 6.7km/h. Easy. Even if your goal is to do 3 or 5 laps, you have your place ! 

For example, on our Backyard in Normandy, two people stopped at 2 laps and the average of all participants is 10.2 laps, no more. 

This loop format, is one of the best formats to test you on longer distances, which is close to the ultra trail. Simply to beat your distance record or run at night safely because you always come back to the base camp every hour and you are never more than 3 km from the start or finish. 

Another important statistic to convince you: an amateur study was conducted in the USA on several backyards and it was shown that most of the runners managed to double their record distance ever covered on this format. 

So, let yourself be tempted, you risk nothing. 

Any hesitation ? You are afraid ?

It’s normal, send us a little message to tell us about it…


Backyards Ultra records
World records
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Courtney Dauwalter - 2020
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Merijn Geerts et Ivo Steyaert (BEL) - October 2022
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French records
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Claire Bannwarth - October 2022
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0 loops
Guillaume Calmettes - 2017
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Backyard ultra in France records
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Claire Bannwarth - World Team Championship 2022
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Christian Mauduit - World Team Championship 2022
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Come run a Backyard Ultra !