الملكان الكاثوليكيان
In this building came to reside different Castilian monarchs, were held synods and councils, and in here were born the youngest daughter of the Catholic Monarchs and future queen of England, Catherine of Aragon, and the German Emperor Ferdinand, son of Joanna "the Mad". In addition, it is famous for being the place where the first meeting between the Catholic Monarchs and Christopher Columbus was held.