Little Hagia Sophia

Little Hagia Sophia (Turkish: Küçük Ayasofya Camii), formerly the Church of the Saints Sergius and Bacchus (Greek: Eκκλησία τῶν Άγίων Σεργίου καί Βάκχου ὲν τοῖς Ὸρμίσδου), is a former Eastern Orthodox church dedicated to Saints Sergius and Bacchus in Constantinople, converted into a mosque during the Ottoman Empire.

This Byzantine building with a central dome plan was erected in the sixth century by Justinian, likely was a model for Hagia Sophia (St. Sophia), and is one of the most important early Byzantine buildings in Istanbul. It was recognized at the time as an adornment to the entire city, and a modern historian of the East Roman Empire has written that the church, "by the originality of its architecture and the sumptuousness of its carved decoration, ranks in Constantinople second only to St. Sophia itself".