It's easy to find this church, converted into a mosque by the Ottomans, located around the corner from Istanbul University, beside the great Valens Aqueduct. It is believed to have been built in the 9th century, and frescos from the Crusader occupation were found and moved to the Istanbul Archaeological Museum. The mosque is usually open; the interior is spacious but a little austere. Nearby, in the backstreets of the poor suburb of Vefa, is the Church of St. Theodore, now known as the Molla Gürani Cami, on Molla Semsittin Sokak off Vefa Cadesi. This former church has an impressive facade, and although it's not often open, inside some mosaics survive in the small domes, with the figures only lightly painted out.
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