The trail leaves the car park where the Campo Base forest park entrance is in the direction of Riaza, leaving the access to the ski resort on the right. The entrance to the La Pinilla apartment complex appears immediately. The route follows the little road that goes up towards the buildings, goes around a line of apartments to the left and, leaving the curve, takes a detour that enters the pine forest. The road has a barrier so that cars do not enter. In the urbanization there are several options and we have chosen the most direct ascent. The wall at the beginning impresses so quickly, with almost no time to warm up your legs, but it takes a few minutes to walk until it connects with an old forest track that also goes up from the buildings and heads towards the peaks. The path passes the course of the Serrano river, next to a water intake, and undertakes a long climb up the slopes of the sierra.