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. It has three radially situated apses and an ambulatory around the central area, surmounted by circular gallery. The circular shape is typical of the early medieval age in Dalmatia. It was built on the Roman forum, and materials from buildings in the latter were used in its construction. Among the fragments which are built into the foundations it is still possible to distinguish the remains of a sacrificial altar on which is written IVNONI AVGUSTE IIOVI AVGUSTO.
The use of the church has varied during its lifetime; during the rule of the Republic of Venice it was a warehouse, as well as during the French occupation and under the Austrians. After the city was annexed to Yugoslavia, it served as an archaeological museum for a short period of time. The building is currently used as the concert venue for the annual International Festival of Medieval Renaissance Music due to the building's interiors and acoustics.
References:The Walls of Constantinople are a series of defensive stone walls that have surrounded and protected the city of Constantinople (today Istanbul) since its founding as the new capital of the Roman Empire by Constantine the Great. With numerous additions and modifications during their history, they were the last great fortification system of antiquity, and one of the most complex and elaborate systems ever built. They were also the largest and strongest fortification in both the ancient and medieval world.
Initially built by Constantine the Great, the walls surrounded the new city on all sides, protecting it against attack from both sea and land. As the city grew, the famous double line of the Theodosian Walls was built in the 5th century. Although the other sections of the walls were less elaborate, they were, when well-manned, almost impregnable for any medieval besieger.