Built in the 12th century, it is the oldest church in Estella. The sanctuary dating from the end of the 12th century is still standing.It has three naves, dating from around the 13th century.The chapel of San Andrés is Baroque and has a Rococo altarpiece.At the foot of the church there are baroque stalls and a font.The exterior cloister has a square plan and in it there are decorated capitals that narrate the life of Saints and Christ, along with plants and animal reliefs.