Bosporus, also know as Bosphorus, is a strait that provides a narrow connection between the Black Sea and the Aegean and Mediterranean seas. It is the separation line between Europe and Asia, and it also separates the largest Turkish city, Istanbul, in two parts. Bosporus is a region with intense commercial maritime navigation because it provides the only passage from the Black Sea region into the Mediterranean.
Bosporus is considered a narrow strait. Its minimal width is 700 meters, and the maximal width is over 3 km. An international convention regulating the maritime traffic through Bosporus states that the strait is an international shipping passage, and thus Turkey has limited rights to restrict navigation through the strait. Bosporus and Dardanelles the two straits that form a small sea called Marmara, which lies between the Black Sea and Mediterranean.