Known as the easternmost arm of the Baltic Sea, the Gulf of Finland is a strategic waterbody. It spans from Finland to the north, Estonia to the south, and Saint Petersburg, Russia, to the east, where the Neva River empties into it. Helsinki and Tallinn are famous cities around the Gulf of Finland, whose eastern parts are controlled by Russia.
In fact, some of the major Russian oil harbours lie close to St.Petersburg, such as Primorsk. The Gulf of Finland is important for Russia, and recently,...
https://www.marineinsight.com/know-more/facts-about-the-gulf-of-finland/