This article focuses on two crucial aspects of the autobiography entitled El río: novelas de caballería(1989),by Guatemalan author Luis Cardoza y Aragón. On the one side, through a practical relation with the theories of authors as Lejeune and De Man, this text takes a deep analysis of the doubtful perspective from which the poet builds his autobiography: an imposible writing that, notwithstanding, it does not prevent him —though still touched by surrealistic spell— from diving completely into this genre. On the second hand, strongly based on the theory of the literary portrait (Iriarte), this study analyzes the assemblage of personas that constructs the gallery of his days, since the narration of his existence gathers many other lives, acts, voices, and personas. El río by Cardoza drinks from the waters of many rivers, its bed formed by the stream of an entire age he lived as a Milky Way citizen.