Ionian Islands (region) party. Ionian Islands (region) The Ionian Islands Region (, , ) is one of the thirteen administrative regions of Greece. The administrative region does not include all of the Ionian Islands; the island of Kythera, which historically was part of the island group, was separated and integrated to the (far away) Attica Region. The population of the Ionian Islands in 2011 was 207,855, decreased by 1,50% compared to the population in 2001. Nevertheless, the region remains the third by population density with 90.1/km² nationwide, well above the national of 81.96/km². The most populous of the major islands is Corfu with
Sea of Marmara , with dimensions .Its greatest depth is . The sea takes its name from Marmara Island, which is rich in sources of marble, from the Greek "μάρμαρον" ("marmaron"), "marble". The sea's ancient Greek name "Propontis" derives from "pro-" (before) and "pontos" (sea), deriving from the fact that the Greeks sailed through it to reach the Black Sea, "Pontos". In Greek mythology, a storm on Propontis brought the Argonauts back to an island they had left, precipitating a battle where either Jason or Heracles killed King Cyzicus, who mistook them for his Pelasgian enemies. The surface salinity of the sea averages