Toklu Dede Mosque

Toklu Dede Mosque is a Byzantine mosque in the Ayvansaray neighborhood of Istanbul, with its south wall preserved within a modern residential building. The structure follows a simple rectangular plan and sits near the shoreline of the Golden Horn.

The building was constructed as a church during Byzantine rule and converted into a mosque after the Ottoman conquest of Constantinople in 1453. This transformation reflected the political and religious changes that swept through the city during that time.

The building carries marks of its Byzantine past that remain visible in the stonework and overall design. These traces show how the structure once served a different purpose and held meaning for people in this area.

The mosque is difficult to visit since most of the building is integrated into a modern residential structure and is not publicly accessible. The site sits in a densely populated residential area near the waterfront where pedestrians can explore the surroundings.

Stamped bricks from the 5th and 6th centuries are built into the walls, taken from earlier structures and reused. This practice shows how builders in Istanbul salvaged materials from older buildings.