The San Pedro stream basin is the ancient valley of Salvanés, a tributary of the Tagus River, where the first groups of farmers and shepherds who inhabited the area since the Bronze Age were located. From the 13th and 14th centuries, the inhabitants of the valley began a process of repopulation towards the higher agricultural fields and founded the current Villarejo de Salvanés, protected by the Order of Santiago that dominated these lands during the process of Christianization after the Reconquista.