The body of water recognized as the world's largest inland sea is the Caspians Sea. Despite being called a "sea," it is actually categorized as a lake due to its enclosed nature and elevated salinity, making it one of the saltiest bodies of water. Located between Europe and Asia, bordered by five countries, it plays a critical role in regional ecology, commerce, and fisheries. The Caspian Sea's unique environment supports diverse species, including sturgeon, known for its production of caviar. It is also significant for oil and gas extraction.