Sea · Germany, Denmark, Sweden
Baltic Sea
The Baltic Sea is an arm of the Atlantic Ocean in northern Europe, with nine countries on its shores. It is one of the largest areas of brackish water in the world – a mix of salt water and fresh water.
Picture credit: Leonhard Lenz (CC BY-SA 4.0) · John Samuel (CC BY-SA 4.0) · Laima Gūtmane (simka… (CC BY-SA 3.0) · Wikimedia Commons
Where is Baltic Sea?
Part of: Atlantic Ocean.
Countries on its coasts: Germany, Denmark, Sweden, Finland, Russia, Poland, Estonia, Latvia, Lithuania.
The story behind it
The water of the Baltic Sea is only a little salty: it has about a fifth as much salt as the great oceans. The sea is also shallow, only about 54 m deep on average. Its deepest spot, the Landsort Deep off the coast of Sweden, goes down 459 m. Every winter parts of the sea freeze, and on average ice covers almost half of it at the coldest time. On the southern shores, people find amber, which was once a much-wanted trade good. Big islands such as Gotland, Öland, Bornholm and Rügen lie in the sea. Cities like St Petersburg, Stockholm, Helsinki and Riga stand on its coasts. Herring and cod swim in the water, and the Baltic ringed seal lives here too.
Find it on the globe
Baltic Sea is there as a name written across its water — tap the water and its card opens. From far away the planet is only a blue ball; detail arrives as you zoom in, and this one appears once you are close enough. Open it on the globe.
Questions children ask
How big is the Baltic Sea?
How salty is the Baltic Sea?
The Baltic Sea contains only about a fifth as much salt as the oceans. In many places its surface water is almost as fresh as the water in a lake.
Does the Baltic Sea freeze in winter?
Yes, parts of it freeze every winter, especially in the north, and now and then almost all of it. On average, ice covers almost half of the sea at the coldest time.
Where these numbers come from
Every figure on this page was checked against public reference sources before publication. Where sources genuinely disagree, the text says so.
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