Giresun Adası is a small, inhabited Turkish island in the Black Sea . It is 1.7 kilometers from the coast and about four kilometers northeast of Giresun . The island is 320 meters long and 237 meters wide, with an area of four hectares . Giresun Adası is also known by the ancient name of Aretias . In the Middle Ages there was a small Byzantine monastery here , the remains of which can still be seen on the island today.