<P> Hagios Demetrios in Thessaloniki, Saint Catherine's Monastery on Mount Sinai, Jvari Monastery in present - day Georgia, and three Armenian churches of Echmiadzin all date primarily from the 7th century and provide a glimpse on architectural developments in the Byzantine provinces following the age of Justinian . </P> <P> Remarkable engineering feats include the 430 m long Sangarius Bridge and the pointed arch of Karamagara Bridge . </P> <P> The period of the Macedonian dynasty, traditionally considered the epitome of Byzantine art, has not left a lasting legacy in architecture . It is presumed that Basil I's votive church of the Theotokos of the Pharos and the Nea Ekklesia (both no longer existent) served as a model for most cross-in - square sanctuaries of the period, including the Cattolica di Stilo in southern Italy (9th century), the monastery church of Hosios Lukas in Greece (c. 1000), Nea Moni of Chios (a pet project of Constantine IX), and the Daphni Monastery near Athens (c. 1050). </P> <P> The cross-in - square type also became predominant in the Slavic countries which were Christianized by Salonikas missionaries during the Macedonian period . The Hagia Sophia church in Ochrid (present - day Macedonia) and the eponymous cathedral in Kiev (present - day Ukraine) testify to a vogue for multiple subsidiary domes set on drums, which would gain in height and narrowness with the progress of time . </P>

Byzantine architecture was devoted to reinforcing the philosophy of mathematics