Chora Church or the Church of the Holy Saviour in Chora is a medieval Byzantine Greek Orthodox church located in Istanbul, Turkey. The original church on this site dates back to the 4th century AD. Between 1077–1081 AD the church was rebuilt by Maria Dukaina, the mother-in-law of the Byzantine emperor Alexius I Comnenus. In the 16th century, during the Ottoman era, the church was converted into a mosque and later in 1948 it became a museum. Chora Church was inscribed as a UNESCO World Heritage Site in 1985 as part of Historic Areas of Istanbul.