Sea of Marmara

The Sea of Marmara, also known as the Marmara Sea, is a small inland sea located entirely within the borders of Turkey. It connects the Black Sea to the Aegean Sea via the Bosporus and Dardanelles straits, separating Turkey’s European and Asian sides. It has an area of , and its dimensions are . Its greatest depth is . The Sea of Marmara is named after the largest island on its south side, called Marmara Island because it is rich in marble (Greek μάρμᾰρον (mármaron) "marble"). In classical antiquity, it was known as the Propontis, from the Greek words pro (before) and pontos (sea), reflecting the fact that the Ancient Greeks used to sail through it to reach the Black Sea, which they called Pontos. In Greek mythology, a storm on the Propontis brought the Argonauts back to an island they had left, precipitating a battle in which either Jason or Heracles killed King Cyzicus, who had mistaken them for his Pelasgian enemies. The surface salinity of the Marmara averages about 22 parts per thousand, which is slightly more than that of the Black Sea, but only about two-thirds that of most oceans. The water is much more saline at the bottom of the sea, averaging a salinity of around 38 parts per thousand, similar to that of the Mediterranean Sea. This high-density saline water does not migrate to the surface as is also the case with the Black Sea,. Water from the Susurluk, Biga (Granicus), and Gönen Rivers also reduces the salinity of the sea, though with less effect than on the Black Sea. With little land in Thrace draining southward, almost all of these rivers flow from Anatolia. The sea's south coast is heavily indented and includes the Gulf of İzmit (İzmit Körfezi), the Gulf of Gemlik (Gemlik Körfezi), the Gulf of Bandırma (Bandırma Körfezi), and the Gulf of Erdek (Erdek Körfezi). There are two main groups of islands in the Sea of Marmara. To the north lie the Princes' Islands, an archipelago made up of the inhabited islands of Kınaliada, Burgazada, Heybeliada, Büyüyada and Sedef Adası and several uninhabited islands including Sivriada, Yassıada, Kaşıkadası and Tavşanadası.