Collines du diable is a late-February trail race in Cahors, in the Lot department of southwest France. Runners choose between 12 km and 25 km, both on hilly natural terrain above the town. The shorter race climbs about 540 meters, while the 25 km route climbs roughly 1050 meters, so even the entry option is not a flat jog. The event suits beginners who want a hard but manageable trail outing, and experienced runners who want a steeper, longer test early in the season.
The course is mostly narrow singletrack, with about 90% of the route on small trails through the Cahors hills. It passes old vineyard land, stone walls, cazelles, the Croix Magne, and viewpoints over the loop of Cahors. One of the clearest local details is the crossing of the Valentré bridge, the medieval stone bridge that gives the race a strong Cahors identity. The race has run across many editions with results listed over a long stretch of past races, and one recorded edition drew 442 starters split between the 12 km and 25 km courses.