Eminönü is a former district of Istanbul in Turkey, now a neighbourhood of Fatih district. This is the heart of the walled city of Constantine, the focus of a history of incredible richness. Eminönü covers roughly the area on which the ancient Byzantium was built. The Galata Bridge crosses the Golden Horn into Eminönü and the mouth of the Bosphorus opens into the Marmara Sea. And up on the hill stands Topkapı Palace, the Blue Mosque (Sultanahmet Camii) and Hagia Sophia (Aya Sofya). Thus Eminönü is the main tourist destination in Istanbul. It was a part of the Fatih district until 1928, which covered the whole peninsular area (the old Stamboul) within the Roman city walls - that area which was formerly the Byzantine capital Constantinople. Since the resident population of Eminönü is low today, it rejoined the Fatih district in 2009.HistoryThe Golden Horn was a natural port, particularly the Eminönü/Sirkeci shore, which being on a peninsula was also eminently defensible. It was this location that led to the foundation of Byzantium, and from here that the city grew, with the oldest neighbourhoods being the port districts along the Golden Horn. In the 12th century, the Byzantine port was also occupied by merchants from Venice, Amalfi, Genoa and Pisa, who eventually acquired their own wharfs and waterfront districts.