The la trans’Aillassaise begins in Aillas, a village in Gironde in south-west France, and is scheduled for April. The race offers a 10 km trail, a 23 km trail, and a 10 km walk, allowing runners and walkers to participate in the same local event.
The 10 km Trail des châteaux ascends approximately 250 meters, while the 23 km Trail Henry IV climbs around 575 meters, presenting a more challenging profile for the longer distance. The walking event, Marche de la Bassane, is also 10 km. Entry fees are 7 EUR for the walk, 11 EUR for the 10 km trail, and 21 EUR for the 23 km trail.