group of nine islands (adalar) in the Sea of Marmara a few miles southeast of Istanbul; they are part of Turkey. There are permanent inhabitants on the smallest island, Sedef Adasi (ancient Antirobethos), and on the four larger islands, Buyukada (Prinkipo, ancient Pityoussa), Heybeli Ada (Halki, ancient Chalcitis), Burgaz Adasi (Antigoni, ancient Panormos), and Kinali Ada (Proti). Buyukada was Leon Trotsky's home for a time after his exile from the Soviet Union in 1929. Heybeli Ada has a branch of the Turkish naval academy.
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