Bati'Run is a race day with a building-trades theme, held at L'Illiade, the Chartres expo park, and organized by FFB Eure-et-Loir. It typically takes place in October, coinciding with Pink October fundraising. The event includes timed running, Nordic walking, a family walk, and children's races. Participants can choose between a 12 km timed event and a 6 km format, welcoming club runners, walkers, families, company teams, and children, not exclusively serious racers.
The course begins at L'Illiade and follows the forest paths of Gasville-Oisème, extending towards Saint-Prest and Champhol. Approximately 80% of the nature course consists of trails, featuring building-themed surprises to connect the race with construction workers and trades. The event supports charity, with profits directed to the departmental Handisport committee and Ligue contre le Cancer for Pink October. Recent editions have attracted over 500 runners and walkers, supported by numerous partners and around 50 volunteers.