Little Hagia Sophia  Istanbul - Dec.2016

Little Hagia Sophia Mosque, is a former Greek Eastern Orthodox church dedicated to Saints Sergius and Bacchus in Constantinople, built between 532 and 536, and converted into a mosque during the Ottoman Empire.
This Byzantine building with a central dome plan was erected in the sixth century by Justinian is one of the most important early Byzantine buildings in Istanbul.
The exterior masonry of the structure adopts the usual technique of that period in Constantinople, which uses bricks sunk in thick beds of mortar. The walls are reinforced by chains made of small stone blocks.
The building, the central plan of which was consciously repeated in the basilica of San Vitale in Ravenna and served as a model for the famous Ottoman architect Mimar Sinan in the construction of the Rustem Pasha Mosque, has the shape of an octagon inscribed in an irregular quadrilateral. It is surmounted by a beautiful umbrella dome in sixteen compartments with eight flat sections alternating with eight concave ones, standing on eight polygonal pillars.
The narthex lies on the west side, opposed to an antechoir. Many effects in the building were later used in Hagia Sophia: the exedrae expand the central nave on diagonal axes, colorful columns screen the ambulatories from the nave, and light and shadow contrast deeply on the sculpture of capitals and entablature.
In front of the building, there is a portico (which replaced the atrium) and a court (both added during the Ottoman period), with a small garden, a fountain for the ablutions, and several small shops.
Inside the edifice, there is a beautiful two-storey colonnade which runs along the north, west, and south sides, and bears an elegant inscription in twelve Greek hexameters dedicated to Emperor Justinian, his wife, Theodora, and Saint Sergius, the patron-saint of the soldiers of the Roman army. For some unknown reason, Saint Bacchus is not mentioned. The columns are alternate of verd antique and red Synnadic marble; the lower storey has 16, while the upper has 18. Many of the column capitals still bear the monograms of Justinian and Theodora.  (Source: en.wikipedia.org)