Istanbul Istanbul Istanbul (, or or ; ), historically known as Byzantium and before 1924 as Constantinople, is the most populous city in Turkey and the country's economic, cultural, and historic center. Istanbul is a transcontinental city in Eurasia, straddling the Bosporus strait (which separates Europe and Asia) between the Sea of Marmara and the Black Sea. Its commercial and historical center lies on the European side and about a third of its population lives on the Asian side. The city is the administrative center of the Istanbul Metropolitan Municipality (coterminous with Istanbul Province), both hosting a population of around 15
Strait of Tartary Strait of Tartary Strait of Tartary or Gulf of Tartary (; ; ; ) is a strait in the Pacific Ocean dividing the Russian island of Sakhalin from mainland Asia (South-East Russia), connecting the Sea of Okhotsk on the north with the Sea of Japan on the south. It is long, 4–20 m (13-66 ft) deep, and wide at the narrowest point. "Tartary" is an older name used by Europeans to refer to a vast region covering Inner Asia, Central Asia and North Asia. The toponym is derived from the Medieval ethnonym "Tartars", which was applied to various Turco-Mongol semi-nomadic