Backyard Ultra Solidaire is a 24-hour loop race held at Parc des Sommets Bromont in Bromont, Quebec. Participants run the same 5.2 km circuit repeatedly, which includes 133 m of elevation gain per lap. The event offers two formats: a competitive "U"ltra option and a more open "S"olidaire option.
In the "U"ltra format, runners must complete each loop in under an hour and then rejoin the start for the next group. Failing to start on time, skipping a loop, or exceeding the time limit disqualifies a runner. The winner is the last participant remaining; if multiple runners finish the final loop, the fastest on that loop is declared the winner. Each loop must be officially recorded for the result to be valid.