The Duomo Vecchio or Old Cathedral (also called La Rotonda because of its round layout) is a rustic circular Romanesque co-cathedral standing next to the Duomo Nuovo (New Cathedral) of Brescia. It is one of the most important examples of Romanesque round church in Italy.
While some claims for an earlier construction exist, the earliest documents state the cathedral was built in the 11th century on the site of a prior church with a basilica layout. It has a circular shape that became rare after the Council of Trent.
In the 19th century, many additions to the original medieval building were removed. The entrance portal is one later addition remaining. It contains the medieval Crypt of San Filastrio, in honor of the beatified Brescian bishop.
Near the entrance, rests the sarcophagus of Bishop Berardo Maggi (1308) made of red marble. The Duomo Vecchio contains l'Assunta(1526) and St. Luke, St. Mark and the sleeping Elijah(1533 - 34) by Moretto da Brescia. It contains a Gathering Manna by Gerolamo Romanino and a Translation of the Bodies of Saints by Francesco Maffei.
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.