The Baltic Sea is a brackish Mediterranean sea located in Northern Europe. It is bounded by the Scandinavian Peninsula, the mainland of Europe, and the Danish islands. The Baltic Sea is connected by man-made waterways to the White Sea via the White Sea Canal, and to the North Sea via the Kiel Canal.
The Baltic Sea might be considered to be bordered on its northern edge by the Gulf of Bothnia, on its northeastern edge by the Gulf of Finland, and on its eastern edge by the Gulf of Riga. These various gulfs can also be considered part of the Baltic Sea. (source)
Thank you Dominika!