The construction of the monastery of Sant Miquel de Fluvià began in the middle of the 11th century, and the church was consecrated in the year 1065. Of the entire monastery, only the church remains, the town’s current parish, a building that stands out for its grandeur. This basilica plan church consists of three naves divided by rectangular pillars crowned with both semicircular apses and a fairly prominent transept. The central nave and transept have a barrel vault, while the side vaults are quarter circles. Of the three apses, covered by a quarter sphere vault, the central one stands out, decorated with seven arches fixed to the wall.
On the exterior, this triabsidal apse presents the typical Lombard decoration; the arches end in small sculpted cantilevers at the top. The current gothic renaissance style facade and the rose window above seem to pertain to alterations from the 16th century. We should assume that the cloister of the old monastery was in the southern part and the different monastic rooms surrounded it.
This church was reinforced in the low medieval or modern period; this is what was indicated by the merits, embrasures and machicolations on the upper part of the building’s wall. The bell tower, which is very reminiscent of the Santa Maria de Ripoll or Sant Martí del Canigó, is a tall Romanesque square-floor tower located on the northern end of the cross and separated from the church. It presents Lombard decoration and saw-shaped friezes
The interior of the temple preserves a Romanesque baptismal font, a holy water font from the late gothic era and a gothic image of the polychromatic alabaster Virgin with Child, possibly from the 15th century.