The Trail du Cirque du Fer à Cheval is a trail race held in March in Arbois, located in France's eastern Jura region. Although its name includes 'horse,' it is a running race offering five different course options instead of a single fixed distance. The event caters to a range of participants, from a 10 km route suitable for novice trail runners to an 84 km ultra covering approximately 3,500 m of elevation gain. This allows the race weekend to accommodate beginners, experienced mountain runners, and those seeking a challenging long-distance run.
The available distances are 10 km, 22 km, 32 km, 46 km, and 84 km. The longest course is sometimes listed as an 80 km UTMB Index race in certain results. This ultra-distance event is approximately 81 km with over 3,200 m of ascent. A recent results table showed 259 finishers, providing a sense of the event's scale without it feeling like a massive urban race. Now in its sixth edition, the event attracts enough participants to be recognized locally as a significant Jura trail gathering.