Ultra Trail du Mont'Af is a 100 km trail race starting in Corcelles-les-Monts, a small village in Côte-d'Or near Dijon in Bourgogne-Franche-Comté. Runners face about 4,000 m of climbing, so this is a long mountain-style trail day rather than a flat road ultra. The race is held around mid-October and can be entered solo or as a relay team of two to four runners.
The route uses the area around Mont-Afrique, with sections through natural terrain, lakes, and ponds near the Dijon metropolitan area. The event keeps numbers tight, with entries capped at 500 participants, and the race base is set up at the Corcelles-les-Monts village hall. It suits experienced trail runners who want the full 100 km challenge, but the relay option also brings in teams who want to share the distance and climbing.