The drainage system of the Granada Basin in southern Spain has evolved from endorheic to exorheic since the basin emerged and became continental in the latest Tortonian (late Miocene). The age of implementation for the recent exorheic, east-west drainage can now be identified by small mammal dating. This drainage configuration began in the latest Pliocene–earliest Pleistocene due to the capture of the Genil River by a Cacín River tributary. It represented an important change in the behavior of the basin and therefore in the geomorphology, as depositional forms and processes were replaced by erosive ones. While the basin was endorheic, sedimentation was active throughout the basin. Afterward the change to exorheic and up to the present, erosion dominates and sedimentation occurs only in some small, fault-controlled depositional depocenters.