The Trail du moulin de la mer is a mid-April trail race held in Matignon, Côtes-d'Armor, Brittany, with starts and finishes at Saint-Germain de la Mer. Participants can select either a 10 km or a 19 km course, suitable for those seeking a shorter coastal run or a more extended journey through the Breton landscape. The 19 km race begins first, with the 10 km race commencing ten minutes later.
The courses incorporate sections of the GR34 coastal path, woodland trails, and some rural roads, ensuring proximity to both the sea and the tranquil natural environment around Matignon. The 19 km route includes an aid station midway with water, sugar, and fruit. All participants receive refreshments at the finish line and are requested to provide their own cups. Each finisher is awarded a prize, and food is available on-site post-race. Recent editions have seen enhancements like improved parking facilities.