The only way to get to islands is by sea: whether Istanbul liners or fast ferries (http://www.ido.com.tr/en/...), available at various hours every day. From European Side of Istanbul, you can take a boat from KabataÅ, while from Asian Side, the piers with a connection to the islands are located in Kadıköy, Bostancı, Maltepe and Kartal. (http://www.tarifeyebak.com) The most frequent departures are from Bostancı especially in winter, which also has private mid-sized boat connection to the islands in addition to liners and fast ferries. (http://www.tarifeyebak.com) See Asian Side article for an extensive detail of how to get to Bostancı from more central parts of the city.
A trip on liners typically take around an hour and a half from European Side, and 45 minutes from Asian Side.
Almost all ferries call at all four major islands in a row, but sometimes they first call at Büyükada, and other times at Kınalıada. Island names are not announced by voice inside the ships, so be sure to check the large signs on the quays to make sure that the island you are about to step on is the one that you want to step on.
