The name "Baltic Sea" derives from the sea's early medieval settlers who called it the "Wendish Sea".
The term appeared in German and Swedish literature in Middle Low German, in which it was synonymous with the "East Sea", the body of water east of the Elbe estuary. In English, the term was introduced in the late 14th century, originally referring to the eastern part of the sea. It was later applied to the entire sea. The coasts of the Baltic Sea are heavily indented with fjords, bays, and lagoons.
The Baltic Sea is bordered by Sweden, Finland, Russia, Estonia, Latvia, and Lithuania. It covers an area of 368,000 km² (142,500 sq mi). And it is also home to the world's largest population of bottlenose dolphins.
