The Mediterranean Sea is almost completely enclosed by land: on the north by Europe, on the south by Africa, and on the east by Asia. It covers an area of approximately 2.5 million square kilometers and is connected to the Atlantic Ocean only by the narrow Strait of Gibraltar. This sea was the 'highway' of the ancient world, facilitating trade and cultural exchange between the Phoenicians, Greeks, Romans, and Egyptians. Because it is nearly landlocked, it has very limited tides and is significantly saltier and warmer than the Atlantic. One of its most striking features is the 'Messinian Salinity Crisis'—a geological event 5 million years ago when the sea dried up almost completely, leaving behind massive salt deposits. Today, it remains one of the world's busiest shipping lanes and a premier global tourism destination, though it faces severe challenges from overfishing and plastic pollution.