CHTITRAIL - Lens is a trail running series in Lens, offering two race distances and a walk on the same morning. The races are short-format trails: a 12 km discovery trail begins at 09:00 and a 25 km short trail begins at 10:00. ENVIRONNEMENT SPORT NATURE organizes the event, which is categorized in French trail running as Trail découverte and Trail court.
The courses appear less mountainous: the 12 km route includes 45 m of elevation gain, and the 25 km route has 131 m. This makes the series a practical option for runners seeking trail terrain without significant climbing. A walking event starts at 10:30, allowing participation for those who wish to join the day without running the race distances.