The Sea o Marmara, cried the Sea o Marmora or the Marmara Sea an aa, an in the context o classical antiquity as the Propontis, is the inland sea, entirely within the borders o Turkey, that connects the Black Sea tae the Aegean Sea, thus separatin Turkey's Asie an European pairts. The Bosphorus strait connects it tae the Black Sea an the Dardanelles strait tae the Aegean. The umwhile forby separates Istanbul intae its Asian an European sides. The Sea haes an aurie o 11,350 km² wi the greatest depth reachin 1,370 m.