The Grand Palace (Büyük Saray) of Byzantine Empire covered a large area including today’s Sultanahmet Square and Blue Mosque towards the Marmara shore. As it was at Topkapi Palace, the rooms of the palace extented with additions built in different periods were decorated with richs mosaics, valuable stones and colums. The importance of Grand Palace started to by 10th century and Blehernai Palace at Ayvansaray started to became more important. Grand Palace was used at this period as official accommadation and meeting palace.
During the latin invasion period of Istanbul (1204 – 1261) Grand Palace was also looted among with many other structures. Because som architectural pieces were torn down during Byzantine period to be used elsewhere, it was ruined until the Conquest of Istanbul. During Ottoman period, the fact that new neighborhoods were founded here and the building of Sultan Ahmet Complex during the time of Ahmet I caused some ruins of the palace to disappear and because of the settlement, the research regarding the palace have always been restricted. From the Grand Palace that included many other structures within is borders, some ruins and the ruined walls of Bukeleleon Palace at Çatladıkapı near Small Hagia Sophia have come until today.