AMonumentIndependent states
Hagia Sophia
A vast domed building completed in 537: a church for nearly a thousand years, a mosque from 1453, a museum from 1934 and a mosque again since 2020.
Hagia Sophia was built in 532–537 on the orders of the Byzantine emperor Justinian I. Its dome, 55 metres above the floor, covered one of the largest enclosed spaces in the world for centuries and marks a turning point in the history of architecture.
After the conquest of 1453 Sultan Mehmed II converted it into a mosque, adding minarets, a mihrab and a minbar. In the 16th century Mimar Sinan strengthened the walls with buttresses, and Ottoman architects developed its dome design in their great mosques.
The building became a museum in 1934 and reopened for worship as a mosque in 2020. It is part of the UNESCO World Heritage Site "Historic Areas of Istanbul".
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Updated: October 2, 2026