The oratory of S. Pellegrino and the church of Santa Maria Assunta were built by the monks of Farfa who run the complex until the 12th century, when it came under the jurisdiction of the bishop of Valva.
The oratory (1263) is prior to the church and externally it has a simple, rustic aspect. On the faĆ§ade and counter facade there are entrances whit small rose windows, which illuminate the interior, together with six grates set along the long flanks.
The interior, however, is a true marvel. The small rectangular hall, with lancet vault, divided by carved pluteuses, arranged in four bays with reinforcing arches, is completely frescoed and can be considered one of the most interesting in the region.
Above a painted curtain that runs around the walls there is a pictorial narration in three registers which relates the life of Christ, the passion of S. Pellegrino, episodes from the Old and New Testaments, Benedictine and medieval saint in general.
The second section of the presbytery walls is occupied by a Bominaco calendar, painted for liturgical use by the monastic community, whilst a great S. Christopher stands out on the counter faĆ§ade. The frescos are attributed to three artists, of different styles and training, commonly known as the Maestro dellĀinfanzia, Maestro della Passione and Maestro miniaturista.