In the early Byzantine period, as wide a diversity of styles is seen in ecclesiastical architecture as in art. Two major types of churches, however, can be distinguished: the basilica type, with a nave flanked by colonnades terminating in a semicircular apse and covered by a timber roof; and the stone-vaulted centralized church, with its separate components gathered under a central dome. The second type the stone-vaulted centralized church was dominant throughout the Byzantine period.
Most Byzantine churches feature a centralized basilica plan, which developed because of the Byzantine fondness for domes. The typical Byzantine church features a great central dome, which may be encircled with smaller domes and half-domes.7 Since a circular dome naturally suggests a centralized building beneath it, the Byzantines compressed the rectangular basilica plan into a centralized layout.
Basil I (867-886), like many of his predecessors, built in the area of the Great Palace, two churches: the New Church and the Church of the Theotokos of the Pharos. These set a fashion in church building and decoration that was to exercise an influence for many centuries.
Neither survives, but something is known of them from written descriptions, and it would seem that both were typical of what was to be the mid-Byzantine style. Broadly speaking, the churches of this age conform to a single type, usually termed the cross-in-square.
The Hagia Sophia Basilica in Istanbul, Turkey is one of the great architectural wonders of the world. It served as the main imperial cathedral of the Byzantine Empire and has been designated as a World Heritage Site by UNESCO. The history of the Hagia Sophia goes back almost 1,500 years and for 1,000 years it was the largest cathedral in the world. It was and remains the epitome of Byzantine architecture and it served as the coronation site of many Byzantine emperors.
The new dome, which is taller and braced with forty ribs, was partially rebuilt after damage in the 859 and 989 earthquakes. Plundered during the Latin invasion following the Forth Crusade in 1204, the church was restored under Andronicos II during Palaeologan rule.
The Episcopal Complex of the Euphrasian Basilica in the Historic Centre of Porec is one of the best examples of early Byzantine architecture and art (mosaics). The basilica was rebuilt from the year 553 under the Byzantine Empire and bishop Euphrasius on the site of the older basilica that had become dilapidated.