Sea · Bulgaria, Georgia, Romania
Black Sea
The Black Sea lies between Europe and Asia and is bordered by six countries. Its deep water holds almost no oxygen, so ancient shipwrecks on the bottom have stayed amazingly well preserved.
Picture credit: Vyacheslav Argenberg (CC BY 4.0) · Wikimedia Commons
Where is Black Sea?
Part of: Atlantic Ocean.
Countries on its coasts: Bulgaria, Georgia, Romania, Russia, Türkiye, Ukraine.
The story behind it
The Black Sea covers about 436 400 km², not counting the smaller Sea of Azov next door, which is joined to it by the Kerch Strait. Big rivers such as the Danube, the Dnieper and the Dniester pour in so much fresh water that the sea is brackish – less salty than the Mediterranean. The lighter, less salty water stays on top of heavier, saltier water, and the two layers hardly mix. That is why more than 90 per cent of the deep water has no oxygen. Without oxygen, old wood rots very slowly, so explorers have found ancient ships in excellent condition, such as a Byzantine wreck called Sinop D. Nearer the surface, common and bottlenose dolphins and harbour porpoises swim. Ships reach the Mediterranean through the narrow Bosporus, the Sea of Marmara and the Dardanelles. Istanbul, Odesa, Varna, Constanța, Sochi and Batumi lie on its shores.
Find it on the globe
Black 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 Black Sea?
The Black Sea covers about 436 400 km², without the smaller Sea of Azov. At its deepest point it is about 2 212 metres deep.
Why are old shipwrecks so well preserved in the Black Sea?
Most of the deep water contains no oxygen, because the upper and lower water layers hardly mix. Without oxygen, wood and other materials decay very slowly, so ancient ships can survive for centuries.
How is the Black Sea connected to other seas?
In the south, the Bosporus, the Sea of Marmara and the Dardanelles lead to the Mediterranean Sea. In the north, the Kerch Strait joins it to the Sea of Azov.
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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