Explore hiking trails around San Agustín del Guadalix, Comunidad de Madrid. The best hike near San Agustín del Guadalix is Collado de Cerromalejo Loop via Pista forestal de la Calle Alta, a 6.0 mile loop in Parque Natural de la Sierra de Guadarrama Norte. San Agustín del Guadalix has population 13849.0.