Ultra-Trail Oise Cosacienne

Trail running in the heart of the Oise

The Ultra-Trail Oise Cosacienne, better known by the acronym UTOC, is a trail running event that starts in Choisy-au-Bac, a town located at the confluence of the Oise and Aisne rivers, at the edge of the Compiègne forest. Organized by AS Cosacienne, this sporting event brings together hundreds of passionate runners each year.

Four distances for all levels

The UTOC offers four courses adapted to all levels of practice:

• 10 km: an introductory course accessible to beginners and families, ideal for discovering trail running gently.
• 20 km: an intermediate course that offers a first technical and physical challenge through forest trails.
• 55 km: a long trail that crosses the forests and valleys of the Oise, offering a demanding sporting challenge.
• 110 km: the ultra-trail, the main event, which constitutes a true endurance challenge through the varied landscapes of Hauts-de-France.

Varied and preserved landscapes

The UTOC courses traverse landscapes of great diversity: dense forests of Compiègne and Laigue, rivers and canals, clearings, picturesque villages, and rolling panoramas. Runners discover remarkable natural heritage, including forest paths, riverside trails, and undergrowth passages.

The spirit of trail running

The UTOC cultivates the values of trail running: self-transcendence, respect for nature, solidarity among runners, and friendliness. Aid stations are set up along the courses, staffed by dedicated volunteers who encourage and support the runners. The atmosphere is warm, and mutual aid among participants is the strength of this event.

AS Cosacienne

AS Cosacienne, a sports club from Choisy-au-Bac, is behind the UTOC. The club, committed to promoting sport in natural environments, mobilizes many volunteers each year to organize this event, which contributes to the sporting reputation of the Oise.