The famous encounter of Juan Ruiz or his fictional character with the four brutal serranas during his pilgrimage in Guadarrama has generated the attention of critics of the LBA for many years. The passage has been approached from different angles of analysis, with a predominantly historical as well as allegorical perspective. Bringing up the well known European medieval tradition and some trends from Islamic literature where the equine world is used to trace comparisons with human beings, especially women, I propose to offer a new meaning for the polemical adjective chata. If one takes into account the coexistence of the Islamic culture in Iberia and the possibility of finding this word in medical treatises about horses, an alternative reading of the passage may be interpreted. With this consideration we can go back and depart not only from Americo Castro's premises about Islamic roots in the LBA but also the most recent studies where critics try to demonstrate how the LBA belongs to a multicultural literary context. It is my contention that this perspective will not only facilitate a reconsideration of the serranas as four apocalyptic equine images within an allegorical reading but also provide a better understanding of its hermeneutical mechanism and historical richness.Keywords Medieval literature Á Equine tradition Á Women El viaje realizado por el personaje del arcipreste a la sierra de Guadarrama, rubricado por los editores modernos De como el Arcipreste fue a provar la sierra, e de lo que le constescio´con la serrana, es uno de los pasajes del Libro de buen
