X Im!possible
Race Info
Runners complete a 6.706 km loop every hour, starting on the hour, until only one runner remains.
Event overview
Date: 18 April 2025
Location: Albisgütli, Zürich
Start time: 12.00
Format: Backyard Ultra
Time limit: open ended – the race continues until one runner complete a loop
Everesting Challenge
The X Im!possible Backyard Ultra is not only one of the toughest Backyards ever designed — it is also a direct path into the Everesting Hall of Fame.
With ~380 m of elevation gain per loop, runners accumulate vertical meters incredibly fast:
6 loops: 1/4 Everesting
12 loops: Basecamp Everesting
24 loops (100 miles): Full Everesting
All vertical gain counts toward official Everesting achievements, making this event uniquely suited for runners aiming to combine the Backyard format with a high-elevation challenge.
Aid & logistics
Aid station, food setup and logistics at the race base are currently being finalized.
Details about food, personal area, drop bags, facilities and crew support will be published soon.
