Santa María Jus del Castillo Church was built in the 12th century on the site of a synagogue, since this was then the Jewish quarter of the city. Its original name was Iglesia de Santa María y de Todos los Santos. It was used as a church until the 17th century. Today it is used as an Interpretation Center of the Romanesque and the Camino de Santiago. It was declared a Site of Cultural Interest.
It is a church with a single nave. The apse and the central body of the church are Romanesque, but the façade and tower are from the Baroque period.
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.