Kos Kos Kos or Cos (; ) is a Greek island, part of the Dodecanese island chain in the southeastern Aegean Sea, off the Anatolian coast of Turkey. Kos is the third largest island of the Dodecanese by area, after Rhodes and Karpathos; it has a population of 33,388 (2011 census), making it the second most populous of the Dodecanese, after Rhodes. The island measures , and is from the coast of the ancient region of Caria in Turkey. Administratively, Kos constitutes a municipality within the Kos regional unit, which is part of the South Aegean region. The principal town of
Arkoi that calls at the island, as well as occasional small ferries to other nearby islands such as Marathi. Arkoi Arkoi (; also Arkioi, Αρκιοί) is a small Greek island which is part of the Dodecanese archipelago. It is situated in the eastern Aegean Sea, close to the Turkish Aegean Coast. The island belongs to the municipality of Patmos, and has a population of 54 inhabitants at the 2001 census. The small population means that there is no real capital, but most inhabitants live close to the main harbour with the rest living scattered around the island on higher ground. The