The Islamic elements of Hagia Sophia can all be found in the lower gallery. The first ones that immediately pop out are the gigantic calligraphic medallions. During a major renovation between 1847 and 1849, Sultan Abdülmecid I added eight new calligraphic medallions. They were done by Ottoman calligrapher Kazasker Mustafa İzzet Efendi and are the largest in the Islamic world at 7.5m in diameter. The medallions contain the names of Allah and Muhammad; the first four caliphs Abu Bakr, Umar, Uthman, and Ali; and Muhammad’s grandchildren Hassan and Hussein.
Where the Christian altar once stood, an Islamic mihrab indicating the direction towards Mecca took its place after the Ottoman conquest of Constantinople in 1453. The mihrab is made of marble and was renovated in the 19th century. On both sides are huge candles brought by Grand Vizier İbrahim Paşa after the conquest of Buda under Süleyman the Magnificent. They originally belonged to the court church of Hungarian King Matthias I. Hanging on the right side are calligraphic panels written by three different Ottoman sultans: Mahmut II, Ahmet III, and Mustafa II.
The Sultan’s Loge is to the left of the altar. The Sultan would perform his prayers there. Nobody is sure who built it or when it was built. To the right of the alter is the Muezzin’s Loge, made of marble and dating back to the 16th century. It was under renovation during most of my visits to Hagia Sophia.
In 1739, Mahmut I built a library inside Hagia Sophia on the south side of the building. The Library of Mahmut I is decorated with İznik and Kütahya tiles from the 18th century. There are also tile panels on both sides of the altar made of 16th century İznik tiles.