Its diverse use
Hagia Sophia was originally built as a Greek Orthodox church, later used as a Catholic cathedral. Then, as Constantinople was conquered by the Ottomans, they rededicated it to a mosque in 1453. Elements that were compatible with Islam were allowed to remain, others were simply covered with mortar or destroyed. Crosses were dismantled and the bell removed from the tower, also followed the construction of the first minarets (minaret is an elevated stand or tower for the caller to prayer at or near a mosque) and a mihrab (a mihrab is the Islamic prayer niche in mosques that indicates the direction of prayer). As early as 1453, one minaret was built on each flank of the church. Two more towers were added in the following decades, but the two oldest were demolished and replaced by new ones in 1573, meaning that the building is now surrounded by four minarets. Also, 25 feet (7.5 meter) round wooden shields adorning the name of the Prophet Muhammad were installed, which are still the largest in the world.