The church of Agia Sophia, dedicated to the Word and Wisdom of God, namely Christ, was built in the 7th or 8th century on the ruins of a 5th century early Christian church. The “Great Church” was the metropolitan church of Thessaloniki until 1524, when it was converted into a mosque and returned to Christian worship after 1912. The great church was modelled on the magnificent church of the same name in Constantinople. The mosaics date from the 8th to the 12th century and testify to the high artistic level of Thessaloniki. The most important mosaic composition, the Ascension of Christ, is found in the dome of the church and was created at the end of the 9th century. After the catastrophic fire of 1890, the Turks repaired the monument and frescoed it with an imitation orthomorphism that is still preserved today.