Little Hagia Sophia

was a Greek Orthodox church dedicated to Saints Sergius and Bacchus in Constantinople, built between 532 and 536 and later converted into a mosque during the Ottoman Empire.

This Byzantine building with centers was Built in the sixth century by Justinian with its dome plan, it is one of the most important early Byzantine buildings in Istanbul. At that time, Prokopius recognized it as an ornament of the entire city, and a modern historian of the Eastern Roman Empire wrote that the church “is the pride of Constantinople, second only to St. Sophia itself, with the originality of its architecture and the sumptuousness of its carved decoration.”

The building stands in Istanbul, in the Fatih district, and in the neighborhood of Kumkapı, a short distance from the Sea of Marmara, near the ruins of the Grand Palace and south of the Hippodrome. Now it is separated from the sea by the Sirkeci-Halkalı suburban railway line and the Kennedy Avenue coastal road.

According to a later legend, during the reign of Justin I, his nephew Justinian was accused of plotting against the throne and sentenced to death, which he avoided after Saints Sergius and Bacchus vouched for Justinian’s innocence. He was freed and restored to his title of Caesar, and in gratitude, he swore that when he became emperor, he would dedicate the church to the saints. The construction of this Church of Saints Sergius and Bacchus between 527 and 536 AD (only shortly before the construction of the Hagia Sophia between 532 and 537 AD) was one of the first acts of the reign of Justinian I.

Shortly after the construction of the church, a monastery of the same name was built next to the building.


The exterior masonry of the building uses the usual technique of that time in Constantinople, which uses bricks embedded in thick mortar beds. The walls are reinforced with chains of small stone blocks.

The structure, whose central plan was 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 Rüstem Pasha Mosque, has the shape of an octagon inscribed in an irregular shape. Above it is a beautiful umbrella dome with sixteen compartments, with eight flat parts alternating with eight concave ones, standing on eight polygonal columns.

In front of the building are a portico (which replaced the atrium) and a courtyard (both added during the Ottoman period), with a small garden, a washing fountain, and several small shops.


Inside the building is a magnificent two-story colonnade that runs along the north, west, and south sides and bears an elegant inscription in twelve Greek hexameters dedicated to the Emperor Justinian, his wife Theodore, and Saint Sergius, the patron saint of St. soldiers of the Roman army. For an unknown reason, Saint Bacchus is not mentioned. The columns are alternately of green antique and red Synnadian marble; the lower floor has 16, while the upper floor has 18. Many capitals of the columns still bear the monograms of Justinian and Theodora.