At the highest point of the village stands the Church of San Valentino, dating back to the Romanesque period. Built on rock and erected on the remains of an early medieval parish church, it is dedicated to the Bishop of Terni, who was martyred on February 14, 273 AD, along the Via Flaminia.
The Romanesque-style façade is enriched by a 16th-century portal, topped by a lunette featuring a fresco of the Madonna and Child, as well as a clock marking the six canonical hours.
Over the centuries, the interior of the church has undergone numerous transformations, making every corner a living testament to the local history.
The interior, featuring a single nave, includes two frescoed niches on the right wall.
The first altar is dedicated to Saint Sebastian, depicted in an unusual iconography with archers shown preparing to shoot their arrows. (Saint Sebastian and Saint Roch were invoked as protectors against plague epidemics.)
The second altar displays Saint John the Evangelist and a Crucifixion attributed to the Master of Casteldilago, influenced by Benozzo Gozzoli and Filippo Lippi. On either side of the Crucifixion, Saint Lucy and Saint Agatha gaze toward the visitors.
The main altar was dedicated to the Holy Crucifix. A 1690 document mentions a Crucifixion scene with the Madonna, Mary Magdalene, and Mary of Clopas.
The walls feature remnants of 15th-century frescoes and three recently restored paintings: The Madonna of Loreto with Saints Francis Xavier, Anthony Abbot, and Nicholas of Bari. The Holy Rosary with Saints Dominic and Catherine of Siena. The Madonna and Child with Saints Anne, Charles Borromeo, and Peter Martyr.
On the left wall stands a statue of Saint Valentine holding Casteldilago.