sentences:  It was recognized at the time by Procopius as an adornment to the entire city, and a modern historian of the East Roman Empire has written that the church "by the originality of its architecture and the sumptuousness of its carved decoration, ranks in Constantinople second only to St Sophia itself".The building stands in Istanbul, in the district of Fatih and in the neighbourhood of Kumkapı, at a short distance from the Marmara Sea, near the ruins of the Great Palace and to the south of the Hippodrome.It is now separated from the sea by the Sirkeci-Halkalı suburban railway line and the coastal road, Kennedy Avenue.