Istanbul is a city known for its historical and beautiful structures. Most of these structures are religious and because Istanbul has hosted many cultures throughout history, these structures took shape with the new culture that had settled down in this area. For this or any related reason, many structures which were built as a Church in the Byzantine period was converted into a mosque after the Ottomans and after a museum during the Republican period.
1-Hagia Sophia Museum
Hagia Sophia was constructed by Emperor Justinian I. during the 6th century. This is the 3rd structure built as Hagia Sophia and the only one that has made it until this day. This structure, which was transformed into a mosque after the Ottomans has been a museum since February 1st, 1935.
This structure, which was transformed into a mosque by the Ottomans during the 18th century is thought to be constructed during the 9th or 10th century, although the exact date is not certain. The first phase of the construction is believed to be dedicated to Theotokos Kyriotissa.
3-Monastery of Stoudios
This is the oldest religious structure in Istanbul that has survived from the time of the Byzantine Empire. It was constructed in 454 in the name of St. John. It was converted into a mosque during the reigning of Beyazid II.
First built as a monastery in 534 by St. Theodosius, the Chora Museum was constructed during the period of Justinian. In 1511 Atik Ali Pasha who was a vizier of Sultan Bayezid II. converted the monastery into a mosque.
5- Koca Mustafa Pasa Sumbul Efendi Mosque
Even though the exact construction date is unknown, it is considered as the 6th century. Its previous name is ”Andreas monastery”. The structure was converted into a mosque in 1486.
6- Arap Mosque
The Arap Mosque is based in Karaköy which we can say is the heart of Istanbul. The previous name of this mosque is the Church of San Paolo. It was built by the Arabs in 717 and is known to be the first Mosque to be built in Istanbul. After the siege it was converted into a church by Dominican priests, the structure began to be used as a mosque after 1475.