The Haghia Sophia (Aya Sofya) is a church dating back to 1228-1263. It houses some very fine frescoes. It is a major sight of the city.
This is the entrance with a portico, where the best frescoes are situated. This fresco represents the evangelists, represented by lion, eagle, bull and angel. It's a new edit of a slide I scanned again and edited in 2018.