The Tyrrhenian Sea is an area of the Mediterranean. It is located west of Italy, between the mainland and the islands of Corsica, Sardinia and Sicily. In the northwest it borders with the Ligurian Sea, in the south it crosses over into the open Mediterranean and on the east and it is connected through the Straits of Messina to the Ionian Sea. The sea has an area of 231,000 km ² and is roughly 3600 m deep. In the Tyrrhenian Sea there are a large number of islands. The Tuscan archipelago lies off the Tuscan coast of Italy, and consists of the main islands of Elba, Giglio, Giannutri, Monte Cristo, Capraia and Gorgona. There are also the small islands of Formiche di Grosseto, Scoglio d'Affrica, Meloria, Cerboli and Palmaiola belonging to the Tyrrhenian islands. The Pontine Islands (Ponza Islands) are located on the southern coast of the Lazio region and are only a few miles away from Naples. The island group includes Ponza, Gavi, Zannone, Palmarola, Ventotene and Santo Stefano. Further south, in front of the Gulf of Naples, are the islands of Procida, Ischia, Capri and Vivara. Off the north coast of Sicily are the Aeolian Islands. The island group includes the inhabited islands of Vulcano, Lipari, Salina, Filicudi, Alicudi, Panarea and Stromboli and several smaller uninhabited islands and cliffs.