As a whole , the structure of Zeyrek Mosque , or Pantokrator Monastery , reflects the most typical example of architecture of the
Byzantine
middle period in Constantinople . The south and the north church have domed cross plan . The apses are polygonal with seven sides and having triple lancet windows flanked by niches . The southern church is the largest one and has to the east an esonarthex which was extended up to the imperial chapel . It is covered by two domes , one over the naos and the other over the matroneum (a separate upper gallery for women) of the narthex . The rich decoration of the church disappeared almost completely and only some fragments of marble in the presbyterium in addition to a beautiful floor in opus sectile made with colored marbles where human and animal figures are represented , survived till today . Also some fragments of colored glass are there and suggest that the windows of this church were made of stained glass with figures of Saints .
The imperial chapel is covered by barrel vaults and is surmounted by two domes too . The northern church is notable for its frieze curved with a dog’s tooth and triangle motif running along the eaves line . Unlike the southern church , the northern one has only one dome .
