A sample of the best Romanesque in Navarre.

It is built in the Romanesque to Gothic transitional style, apparent in the combination of elements from both styles inside.

It is a simple church. The richly ornamental northern front is in the Romanesque style and is considered one of the best in Navarre. The most interesting elements are the reliefs on either side of the front, which represent scenes from the Resurrection and the struggle of the Archangel St. Michael. The interior houses a Gothic reredos painted on stucco. It serves as the grave of the marquis of Muruzábal and Eguía. Of note among the sculptures on the reredos is a 17th century San Crispín.