Building began in the last quarter of the 12^th century and continued through to the 18^th century. It sits atop a rocky outcrop known as “La Mota” (The Mount), which lends it the appearance of a fortress. The San Miguel quarter sprang up in the area around the church, opposite which a weekly Thursday market was held, a tradition that remains to this day in a nearby square.

The church is composed of three naves with a chancel that comprises three apses on the outside and two more on the inside. The naves on either side present rib vaults (14^th century) while the central nave contains stellar vaults in a Gothic style (16^th century).

The whole of the north portico is considered a jewel of the late Romanesque period in Spain, and was created between 1187 and 1192 by various artists, with a complex iconographic programme. The portico itself comprises five round archivolts with figurative decoration. These rest on columns with figurative capitals that narrate the childhood of Jesus. In the tympanum we see Christ in Majesty surrounded by the tetramorph (a representation of the four evangelists) next to the Virgin and Saint John.

On both sides of the portico lie two reliefs of exceptional quality that announce the Gothic period: to the left, the archangel Michael defeating the devil and weighing the souls at the Last Judgment; to the right, the Three Marys visiting the empty tomb, symbol of the resurrection of Christ. Above these reliefs lie the apostles.

Inside the church, of particular note are the main altarpiece, Baroque in style with the exception of the Gothic central image of Saint Michael, and the altarpieces of Saint Helen (1416) and the Mass of Saint Gregory.

Outside the church itself, a Gothic tower from the 14^th century, which houses the chapel of Saint George, is particularly noteworthy.