The interior frescoes, from the 13th-15th centuries, include some of the most ancient representations of the martyrdom of St. Thomas Becket, by Alberto Sotio, and of St. Francis.
Di fresco bagian dalam, yang berasal dari abad ke-13-15, termasuk beberapa representasi kemartiran paling kuno St. Thomas Becket, oleh Alberto Sotio, dan St. Fransiskus.