The predominant sea in Eastern Europe is the Black Sea. Bordered by countries such as Bulgaria, Romania, Ukraine, Russia, Georgia, and Turkey, the Black Sea plays a critical role in the region's maritime trade and ecological system. It is connected to the Mediterranean Sea through the Bosporus Strait and the Sea of Marmara, serving as a vital waterway for commerce and naval activity. The Black Sea is also notable for its unique biodiversity and historical significance, as it has been a crossroads of various cultures and civilizations throughout history.