Zeyrek Mosque is the largest Byzantine church still standing in Istanbul after Hagia Sophia, and it is really three churches built shoulder to shoulder. Inside, the space feels tall and bare, its brick arches stripped back to bone. Underfoot lies its greatest treasure, and you will mostly not see it. A floor of coloured marble, among the finest to survive from Byzantium, lies under carpet so that footsteps do not grind it away. A long restoration has left the interior quiet and luminous. Outside, the mosque stands amid steep lanes of leaning wooden houses with the Golden Horn glinting below.
Empress Eirene raised the first church in the twelfth century for the Monastery of Christ Pantokrator. After her early death John II Komnenos added a second and joined the pair with a domed chapel, a mausoleum where emperors of two dynasties were laid to rest. The monastery also ran a hospital renowned far beyond the city. After 1453 the complex passed to a scholar named Molla Zeyrek, whose lessons gave the mosque and the hill around it their name. The streetscape outside is among the oldest left in Istanbul.