Trail Series Colldejou is a mountain-running event held in Colldejou, Province of Tarragona, Spain, with routes in the Colldejou area and the Sierra de Llaberia. It is part of the Trail Series Costa Daurada circuit and provides 5 km, 10 km, and approximately 21 km trail options, along with a 10 km walk. The 10 km route is available for both runners and walkers, whereas the 21 km race is exclusively for runners.
The climbing is central to this event. The 10 km course involves a gain of about 590 metres and ascends Mola de Colldejou. The 21 km course has a gain of approximately 1,200 metres and also includes Mola de Llaberia. The routes traverse protected natural areas, avoiding heavily road-based terrain, making the event suitable for those seeking a concentrated yet steep Costa Daurada trail race. Its inaugural edition attracted over 150 participants, with Raúl Ramírez of Club Triatlón Cambrils winning the 10 km race in 55:25.