The largest lake in the world is comparable in size to the country of Japan. There are over 304 million lakes globally, containing either stagnant or slow-moving water.
Many of the world’s largest lakes can be classified as inland seas, although they are still enclosed by land and have connections to the oceans through rivers or narrow passages.
The Caspian Sea holds the title of the world’s largest lake, spanning a surface area of 386,400 sq km (149,200 sq mi) and straddling the continents of Europe and Asia.
This massive body of water is bordered by Kazakhstan, Russia, Azerbaijan, Iran, and Turkmenistan, with its surface lying approximately 27 meters below sea level.
For perspective, the Caspian Sea dwarfs Lake Superior, which is situated on the Canada-US border and covers an area of 82,000 sq km (31,660 sq mi).
The Caspian Sea accounts for approximately 44% of the total global lake water volume and is estimated to be around 30 million years old, becoming landlocked roughly 5.5 million years ago. The primary freshwater source for the Caspian Sea is Europe’s longest river, the Volga, which flows into the massive lake.
Thanks to this freshwater inflow, the Caspian Sea’s water is mostly fresh. More than 130 rivers, including the Ural River and the Kura River, feed into the Caspian Sea.
The lake is dotted with numerous small islands, primarily located in the northern region and near the shores, but none are found in the deeper sections.
Baku, the capital of Azerbaijan, stands as the largest city along the Caspian Sea, accompanied by other notable cities like Astara in Iran, Atyrau in Kazakhstan, and Derbent in Russia.
The Caspian Sea is a habitat to various species, renowned for its caviar and oil resources. Unfortunately, pollution stemming from the oil sector and dams constructed on rivers that flow into the lake have negatively impacted its ecosystem.
Due to the effects of global warming, reports suggest that the sea’s depth could decrease by nine to 18 meters in the future.
The Caspian Sea hosts a diverse array of flora and fauna, including over 850 animal species and more than 500 plant species, many of which are unique to the region. The lake is home to six critically endangered sturgeon species, alongside the distinctive Caspian seal and beluga.