The decoration of the apse, chancel and side wall of the gospel consists of mural paintings depicting scenes from the life of Christ and the Virgin.
It is attributed to the so called Master of San Felices in the same way as other temples of southern Cantabria northern Palencia and Burgos.
The existing inscription under the painting of the Last Supper allows us to know exactly the date they were made, 1483 (or 1484).
The image of Our Lady and Child (XIIIth. century) is currently at the parish museum in Aguilar de Campoo.