Rando Trail de Trept is a small nature trail race held in Trept, located in the Isère department of Auvergne-Rhône-Alpes, France. It typically takes place in spring, with its next edition scheduled for mid-April. The race offers participants two short trail courses: a 10 km option with approximately 230 m of elevation gain, and a 20 km option with approximately 480 m of elevation gain.
The routes are predominantly off-road, with about 90% of the distance on paths and through wooded areas. The organizers characterize the terrain as wild trails, including climbs, runnable sections, and singletrack. This format appeals to runners seeking a focused trail running experience rather than a road race. The event is organized by the Rando Trail Trept association, providing aid stations and a bag drop service. The location also offers proximity to Lake Paladru and the Château de Virieu.