Istanbul, formerly known as Byzantium and Constantinople, holds a unique geographical distinction as the only major city in the world situated on two continents: Europe and Asia. The city is divided by the Bosphorus Strait, a narrow natural waterway that connects the Black Sea with the Sea of Marmara. While Ankara is the official capital of Turkey, Istanbul remains the country's cultural and economic heart. The European side of the city contains the historic center with landmarks like the Hagia Sophia and Blue Mosque, while the Asian side is primarily residential and industrial. This transcontinental position has made Istanbul a strategic bridge for trade and culture for over 2,500 years. Interestingly, while the city spans two continents, Turkey as a nation is categorized as transcontinental, with about 3% of its land in Europe and 97% in Asia. Residents can commute between continents in minutes via bridges, tunnels, or ferries.