Sancaktar Hayrettin Mosque

Sancaktar Hayrettin Mosque (Sancaktar Hayrettin Câmîi, also Sancaktar Hayrettin Mescidi, where Mescit is the Turkish word for a small mosque, or Sancaktar Mescidi) is part of a former Eastern Orthodox monastery converted into a mosque by the Ottomans. It is generally believed that the small building belonged to the Byzantine Monastery of Gastria ( , Monē tōn Gastríōn, meaning "Monastery of the Vases"). The edifice is a minor example of Palaiologan architecture in Constantinople, and is important for historical reasons.

Mosque data from Wikidata (CC0). Summary from Wikipedia (CC BY-SA).