The Guadiana River receives a fantastic human origin in the account Don Quixote brings back from the Cave of Montesinos. Rather than presenting the river as mere geography, the tale makes its course the continuing expression of an enchanted squire’s grief: Guadiana is transformed into water, disappears underground, and returns to the surface in intervals.

Legendary Origin

Montesinos tells Durandarte that Merlin has kept them and many others enchanted for more than five hundred years. Guadiana, Durandarte’s squire, mourns his master’s fate and is changed into a river. When he reaches the surface and sees the sun, grief at leaving Durandarte drives him back into the earth. Yet, as Montesinos explains it, the river cannot escape its natural course; from time to time it emerges again into daylight.

Course and Character

The river’s waters are joined by those of the Lakes of Ruidera, whose origin is also woven into the enchantment: Merlin changed the grieving Ruidera and her daughters and nieces into lakes. With these waters and others, the Guadiana makes its way into Portugal. Montesinos describes it as melancholy throughout its journey, taking no pride in producing delicate fish and yielding only coarse, tasteless kinds, unlike those of the golden Tagus. The contrast gives the imagined river a temperament as well as a route: its landscape carries the sadness of the story that created it.

The River as a Discovery

After the cave episode, Sancho Panza counts learning the source of the Guadiana—previously unknown to humankind—among the benefits of travelling with Don Quixote of La Mancha. His claim turns the marvel into mock scholarship: the river’s origin becomes material for a proposed Spanish Ovid, while Durandarte’s words are also treated as evidence for a history of playing cards. The episode thus presents the Guadiana’s enchanted origin as both a memorable explanation of the landscape and an object of comic antiquarian certainty.