The architecture of the Byzantine or Eastern Roman Empire which developed from Early Christian and late Roman antecedents in the 4th cent., flourished principally in Greece, but spread widely and lasted throughout the Middle Ages until the fall of Constantinople to the Turks (1453). It is characterized by large pendentive-supported domes, round arches and elaborate columns, richness in decorative elements, and color. The most famous example is the Hagia Sophia in Istanbul (532 537).