The Persian Gulf (, ), sometimes called the (), is a mediterranean sea in Western Asia. The body of water is an extension of the Arabian Sea located between Iran and the Arabian Peninsula. It is connected to the Gulf of Oman in the east by the Strait of Hormuz. The Shatt al-Arab river delta forms the northwest shoreline. The Persian Gulf has many fishing grounds, extensive reefs (mostly rocky, but also coral), and abundant pearl oysters, however its ecology has been damaged by industrialization and oil spills. The Persian Gulf is in the Persian Gulf Basin, which is of Cenozoic origin and related to the subduction of the Arabian Plate under the Zagros Mountains. The current flooding of the basin started 15,000 years ago due to rising sea levels of the Holocene glacial retreat. Geography The International Hydrographic Organization defines the Persian Gulf's southern limit as "The Northwestern limit of Gulf of Oman". This limit is defined as "A line joining Ràs Limah (25°57'N) on the coast of Arabia and Ràs al Kuh (25°48'N) on the coast of Iran (Persia)". This inland sea of some is connected to the Gulf of Oman in the east by the Strait of Hormuz; and its western end is marked by the major river delta of the Shatt al-Arab, which carries the waters of the Euphrates and the Tigris. In Iran, this is called "Arvand Rood", where "Rood" means "river". Its length is , with Iran covering most of the northern coast and Saudi Arabia most of the southern coast. The Persian Gulf is about wide at its narrowest, in the Strait of Hormuz. Overall, the waters are very shallow, with a maximum depth of and an average depth of . Countries with a coastline on the Persian Gulf are (clockwise, from north): Iran; Oman's Musandam exclave; the United Arab Emirates; Saudi Arabia; Qatar, on a peninsula off the Saudi coast; Bahrain, an island nation; Kuwait; and Iraq in the northwest. Various small islands also lie within the Persian Gulf, some of which are the subject of territorial disputes between the states in the region. Exclusive economic zone Exclusive economic zones in the Persian Gulf: Coastlines Countries by coastline length: Islands The Persian Gulf is home to many islands such as Bahrain, an Arab state. Geographically, the biggest island in the Persian Gulf is Qeshm island, belonging to Iran and located in the