The imaginative elegance of its gallery-portico and the sculptures on the capitals are the two most outstanding features of the church of Nuestra Señora del Rivero, the second oldest church in San Esteban de Gormaz.

This is the town's second Romanesque church and is built in ashlar stone with a nave (reformed in modern times), presbytery and semicircular apse, as well as other subsequent additions such as the niche with the figure of the Virgin, and the sacristy.
The most interesting aspect of the church is the porticoed gallery protecting the main façade, comprising eight semicircular arches in addition to the central arch (the three easternmost arches have recently been rebuilt) supported on plain columns and capitals carved with a wide variety of animal motifs (monkeys, birds, combat scenes, turbaned figures and a fish-mermaid).
The doorway itself is designed with a semicircular arch and three archivolts decorated with wreathed batons supported by columns and imaginatively historiated capitals, featuring a monkey, snake, violinist and a dancer, among other motifs.