The first references to this monastery date from the 8th century, although in its current configuration it is presented as a work from the 13th century with important reforms and extensions from the Baroque period. Tradition indicates that the foundation of the monastery dates back to the year 780, being linked to the figure of Aldegaster, supposed bastard son of King Silo, being the great promoter of the Alfonso IX center, who in 1222 established the passage through Oubona as mandatory for pilgrims to Santiago de Compostela.
The Romanesque church has a large semicircular arch doorway with archivolts, on whose roof two flat windows open on two superimposed levels, finishing all this with a large triple-hollow belfry, crowned by an iron cross. Inside, the temple has three naves that end in an apse. Presiding over the temple, a great crucified Christ, suspended from the ceiling, from the Romanesque period.
From the church you can access the cloister, dating from 1659, never finished, and built on the basis of a succession of rough columns and semicircular arches on the ground floor, with windows on the upper level. From the outside, the cloister is accessed through an access located to the right of the church door. It has two semicircular arches on the ground floor and on the upper floor there are two barred windows between which the shields of Castilla y León are arranged and a niche with the image of Saint Benedict.
The Oubona monastery was declared an Asset of Cultural Interest in 1982.