The interior of the mosque produces an effect of extraordinary massiveness, with its bulky piers supporting the dome, with the walls which join these piers to the walls of the church and screen off the aisles from the open space beneath the dome. Except for the two inner columns of the porch, not a single pillar is to be seen. The aisles are narrow, and their ceilings low; they are surmounted by a gallery, from which you look through low, arched apertures into the nave. The Turks have placed a wooden stage in the northern arm of the church, between the two walls which screen off the aisle. This erection faces their altar, and is reserved for their women; you reach it by a staircase placed inside the building, in front of the north-east entrance. A doorway leads from this wooden structure into the old gallery over the aisle, through which you pass to the women's gallery in the original design, which fills the space above the ceilings of the narthex and exo-narthex on the western side of the mosque. Two lofty vaulted openings display the interior to this gallery; while the wall between narthex and exo-narthex is pierced by three arches in a similar style. The door on the west in the storey below, which in Christian times gave access through these outer spaces into the body of the church, is no longer used, now that the religious focus of the building has been changed from the apse to the southern arm between the aisles. The exo-narthex has a width of 18 feet, and the narthex of 9 feet 7 inches. The piers upon which repose the vaulted ceilings of these courts are of such thickness that the entire space, measured from the inner side of the outer wall to the outer side of the wall of the nave, amounts to 37 feet 5 inches. The interior measurements of the church proper are a length of 93 feet 6 inches from the commencement of the nave to the head of the apse, and a breadth of only 50 feet 5 inches. It is well lit from windows in the apse and along the walls; but the twelve windows in the dome are small. Beautiful marble plaques of various colours, and designs in mosaic, may still be admired in the apse; but there is an almost total lack of ornament elsewhere. As to the date of the building, it is ascribed by Texier to the Grand-Comneni; with much less knowledge I hesitate to offer the opinion that the design belongs to an earlier period.