Old temple of San Nicolás, today of the Franciscan fathers, configured along a wide temporal space, with origins in the 12th century, in the Romanesque period, and ending in the 18th, in the middle of the Baroque.
From the early Romanesque stage the western façade is preserved, with the nave and apse in Renaissance style, from the 16th-17th century, while from the Baroque period it is the sacristy attached to the nave.
The plant of the temple is rectangular, with a single nave with a raised choir at the feet and a polygonal head, with side chapels. On the Romanesque façade there are various decorative elements (especially geometric) in the corbels of the roof and in the archivolts. Topping the main façade there is a bell tower with three holes.
Pedro Menéndez de Avilés, prodigal son of the city of Avilés, is buried in this church for his exploration work in Florida, recently incorporated into the kingdom of Spain in the 16th century.