Toklu Dede Mosque

The origin of this building, which was erected at the northern foot of the sixth hill of Constantinople in the neighborhood of ta Karianou,[3] part of the Blachernae quarter, is obscure.

[1] After the Fall of Constantinople to the Ottomans in 1453, between the end of the 15th and the beginning of the 16th century the church was converted into a small mosque (Mescid) by Toklu Ibrahim Dede, a former soldier of Mehmed the Conqueror,[8] who was the custodian of the nearby türbe of Ebû Șeybet ül Hudrî, like the more famous Abu Ayyub al-Ansari (the standard bearer of Muhammad), a companion of the Prophet.

The building had a rectangular plan with external sides of 14.2 m and 6.7 m.[1] A square single nave was surmounted by a barrel vault and covered at its center by a dome with a diameter of about 4 m.[7][10] This was supported by arches carried by angular piers.

[10] The nave was preceded by an esonarthex and ended towards East with a bema and a polygonal apse adorned internally and externally with shallow niches.

[7] The church was decorated with 14th-century frescoes, among them images of the Saints Eleuterus, Abercius, Polykarpos, Spyridon, Procopius and Nicetas, some of them framed in medallions.