This Byzantine church with a central dome plan was erected in the 6th century and was a model for the Hagia Sophia, the main church of the Byzantine Empire. It is one of the most important early Byzantine architectural example in Istanbul.
The construction of the Church of Saints Sergius and Bacchus, between 527 and 536 AD (only a short time before the erection of the Hagia Sophia between 532 and 537), was one of the first acts of the reign of Justinian I.
After the conquest of Constantinople by the Ottomans in 1453, the church remained untouched until the reign of Bayezid II. Then (between 1506 and 1513) it was converted into a mosque.
Due to the increasing threats to the building's static integrity, it was added to the UNESCO watch list of endangered monuments some in 2002. The World Monuments Fund added it to its Watch List of the 100 Most Endangered Sites in 2002, 2004, and 2006. After an extensive restoration which lasted several years and ended in September 2006, it has been opened again to the public and for worship.
However it is very close to Sultanahmet historical area the church of Little Hagia Sophia is one of the least visited monument in the area and the church, its environment is really attractive and peaceful especially with the café and small workshops in courtyard.
*The Small HAgia Sophia mosque is right behind the Blue Mosque located in the Kucuk Ayasofya street, after passing through the Arasta Bazaar, and continuing straight about 500 meters you will see its characteristic flattish dome rising at the base of the hill.
Since it is still active mosque it is open every day of year from 08.00 am to 08.00 pm. But it is closed during the praying time temporarily for visitors.
*Women need to cover the head and therefore it is convenient to carry a scarf with you if you do not want to use the one offered in the mosque and both men and women need to be dressed properly which means shoulders and legs are asked to be covered.
*No entrance fee