San Miguel Church is built in the Romanesque to Gothic transitional style, apparent in the combination of elements from both styles inside. 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.
References:The Church of St Donatus name refers to Donatus of Zadar, who began construction on this church in the 9th century and ended it on the northeastern part of the Roman forum. It is the largest Pre-Romanesque building in Croatia.
The beginning of the building of the church was placed to the second half of the 8th century, and it is supposed to have been completed in the 9th century. The Zadar bishop and diplomat Donat (8th and 9th centuries) is credited with the building of the church. He led the representations of the Dalmatian cities to Constantinople and Charles the Great, which is why this church bears slight resemblance to Charlemagne's court chapels, especially the one in Aachen, and also to the Basilica of San Vitale in Ravenna. It belongs to the Pre-Romanesque architectural period.
The circular church, formerly domed, is 27 m high and is characterised by simplicity and technical primitivism.