Hagia Sophia

A world famous

Hagia Sophia is the main church in Byzantine capital of Constantinople modern day Istanbul, and was built to replace an earlier version that had burnt down in riots in 532. It has remained in its 6th century structure up until the present day.

It was a feat of architectural daring that went unmatched for 1000 years and the origins are unknown. The design places a circular dome on a square foundation. The weight of the dome is concentrated across 40 ribs. Forces are channelled by ribs and could only be supported by 4 corners of square plan with transition between circle and square made by pendentives (triangular pieces of masonry). The internal structure measures 76m (250ft) long and over 30m (100ft) wide. Unfortunately much of the original decoration has been lost during periods of iconoclasm and church conversion to a mosque in 1453.