The Church of Hagia Theodosia, known today as Gul Mosque, is one of the most atmospheric stops on the Fener and Balat walking tour. Built in the 11th century, the building was dedicated to St. Theodosia, a Byzantine woman who became a martyr during the early years of the Iconoclasm period.
In the 8th century, Emperor Leo III ordered the destruction of icons, believing they led to idolatry. Theodosia, a devout iconophile, resisted imperial soldiers who attempted to remove an icon of Christ from Constantinople’s Chalke Gate.
She was killed during this act of defiance and was later canonized as a saint by the icon-supporting wing of the Byzantine Church. This church was constructed centuries later in her memory, and it remains one of the few surviving Byzantine monuments in Istanbul.
Church of Hagia Theodosia (today Gul Mosque)
Walking into Gul Mosque is like stepping back in time. Unlike the bright interiors of Ottoman mosques, Byzantine churches are typically dim and almost mysterious. The low lighting and thick stone walls of the Church of Hagia Theodosia instantly transport visitors into the Middle Ages.
On my Fener and Balat tours, we use this quiet atmosphere to talk about the dramatic history of the Byzantine Iconoclasm and how it shaped the empire’s religious landscape.
I have been guiding tours through Fener and Balat since 2008, and Gul Mosque has always held a special place in these walks. For years, an elderly caretaker—an ex-taekwondo champion—would open the doors for us even when the building was closed.
Sadly, he passed away a few years ago, making access to the mosque less predictable. However, we are still often able to enter, and when we do, we usually have the building entirely to ourselves.
The Dome of Gul Mosque is Worth Seeing!
The name “Gul Mosque” (meaning Rose Mosque) is believed to date back to the Ottoman conquest of Constantinople, when soldiers reportedly found the church adorned with roses. This detail adds a poetic note to an already mystical setting.
The dome of Gul Mosque was rebuilt by the Ottomans after it collapsed in an earthquake. The geometric ornamentation of the dome, faithful to the original, is particularly striking.
Furthermore, the arches supporting the dome on all four sides bear the Star of David, as seen in the image above. While the presence of a Jewish symbol may surprise visitors, this star is a common sight in Ottoman mosques.
The Ottomans considered Jews and Christians to be people of the book and did not exclude their traditions. While there were no human-like statues or paintings in the mosques, there were motifs bearing the traces of many different cultures.
Conclusion
The Church of Hagia Theodosia is one of the few places in Istanbul where visitors can still feel the authentic atmosphere of a medieval Byzantine church. Its dimly lit interior, deep historical roots, and tranquil setting make it a truly unforgettable stop on the Fener and Balat walking tour.
If you would like to learn more about the history, hidden gems and unique stops of the Fener and Balat walking tour, you can read the full Fener and Balat Tour Overview here.
If you’d like to explore this hidden gem and hear more about the dramatic events of the Iconoclasm period in an intimate setting, you can join me on a private guided Fener and Balat tour.