Istanbul is the largest city in Turkey, straddling the Bosphorus—one of the world's busiest waterways—in northwestern Turkey, between the Sea of Marmara and the Black Sea, Istanbul is a transcontinental city, with one third of its population living in Asia but its commercial and historical center in Europe. Anadolu Kavağı is a small fishing village on Macar Bay the narrowest stretches of the Bosporus.