Fountain. Blue Mosque on the background

Istanbul, historically known as Byzantium and Constantinople, is the largest city of Turkey and the 3rd largest in Europe. It is located on the Bosphorus Strait and encompasses the natural harbor known as the Golden Horn, in the northwest of the country. It extends both on the European (Thrace) and on the Asian (Anatolia) sides of the Bosphorus, and is thereby the only metropolis in the world that is situated on two continents. During its long history, Istanbul has served as the capital of the Roman Empire (330–395), the Eastern Roman (Byzantine) Empire (395–1204 and 1261–1453), the Latin Empire (1204–1261), and the Ottoman Empire (1453–1922). The historic areas of the city were added to the UNESCO World Heritage List in 1985. Istanbul houses thousands of mosques, as well as numerous churches, synagogues and other religious structures.