The Mediterranean Sea is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean Basin and almost entirely enclosed by land: on the north by Western and Southern Europe and Anatolia, on the south by North Africa, and the east by the Levant. The Mediterranean Sea has played a central role in the history of Western civilization. Although the Mediterranean is sometimes considered a part of the Atlantic Ocean, it is usually referred to as a separate body of water. Geological evidence indicates that around 5.9 million years ago, the Mediterranean was cut off from the Atlantic and was partly or wholly desiccated over some 600,000 years during the Messinian salinity crisis before being refilled by the Zanclean flood about 5.3 million years ago.
The Mediterranean Sea covers an area of about 2,500,000 km2 (970,000 sq mi), representing 0.7% of the global ocean surface. In oceanography, it is sometimes called the Eurafrican Mediterranean Sea, the European Mediterranean Sea or the African Mediterranean Sea to distinguish it from Mediterranean seas elsewhere. Still, its connection to the Atlantic via the Strait of Gibraltar—the narrow strait that connects the Atlantic Ocean to the Mediterranean Sea and separates the Iberian Peninsula in Europe from Morocco in Africa—is only 14 km (9 mi) wide. The Mediterranean Sea encompasses many islands, some of them being of volcanic origin. The two by far largest islands are Sicily and Sardinia.
The Mediterranean Sea has an average depth of 1,500 m (4,900 ft), and the deepest recorded point is 5,267 m (17,280 ft) in the Calypso Deep in the Ionian Sea. It lies between latitudes 30° and 46° N and longitudes 6° W and 36° E. Its west-east length, from the Strait of Gibraltar to the Gulf of Iskenderun, on the southeastern coast of Turkey, is about 4,000 kilometres (2,500 mi). The north-south length varies significantly between different shorelines, and only straight routes are considered. Also, including longitudinal changes, the shortest shipping route between the multinational Gulf of Trieste and the Libyan coastline of the Gulf of Sidra is about 1,900 kilometres (1,200 mi). The water temperatures are mild in winter and warm in summer and give a name to the Mediterranean climate type due to most precipitation falling in the cooler months. Its southern and eastern coastlines are lined with hot deserts not far inland, but the immediate coast on all sides of the Mediterranean tends to have solid maritime moderation.
The history of the Mediterranean region is crucial to understanding the origins and development of many modern societies. The sea was an important route for merchants and travellers of ancient times, facilitating trade and cultural exchange between peoples of the region. The Roman Empire maintained nautical hegemony over the sea for centuries.
The countries surrounding the Mediterranean in clockwise order are Spain, France, Monaco, Italy, Slovenia, Croatia, Bosnia and Herzegovina, Montenegro, Albania, Greece, Turkey, Syria, Lebanon, Israel, Palestine, Egypt, Libya, Tunisia, Algeria, and Morocco; Malta and Cyprus are island countries in the sea. In addition, the disputed territory of Northern Cyprus, and some enclaves, notably Gibraltar and Ceuta, have coastlines on the sea. Alexandria is the largest coastal settlement. The drainage basin encompasses many other countries, the Nile being the longest river ending in the Mediterranean Sea.