Fine ex­ample of By­zan­tine ar­chi­tec­ture. Built in the form of a Greek cross, with a 42 ft dia­me­ter dome in the cen­ter and smal­ler domes ri­sing over each arm. It was com­ple­ted in 1071.

View up­wards into one of the smal­ler domes. The inner sur­faces of all the domes are co­vered with Bi­bli­cal pic­tu­res in glass mo­saics. The inner shells of the domes are less than half the height of the outer shells which are sup­por­ted on cir­cu­lar drums.