Bosporus

The Bosporus is a narrow, naturally occurring strait in Turkey that connects the Black Sea to the Sea of Marmara. It serves as a vital waterway, controlling maritime traffic between Europe and Asia. The strait is about 19 miles (30 kilometers) long and only 2 miles (3.7 kilometers) wide at its narrowest point, making it unique in geography. It also divides the city of Istanbul into European and Asian sides. The Bosporus is strategically important for trade, military, and transportation, and features several bridges and tunnels that facilitate movement between the continents.