The islands of Sehir Adalari are enchanting and mysterious, but not in summer. The latter are usually only interested in the place as a location for sunning themselves on the beach and buying cold ice cream. In the spring and autumn the island is a different place altogether. On Castle Island there are many ruins dating from early Carian to the last Byzantine occupation. This is the site of ancient Kedreai, part of the Rhodian Confederacy and later part of Roman Asia Minor. The small beach on the west of the island is known as Cleopatra's Beach.
The ruins on the island are romantically situated amid olive groves, and the small theatre is sited with a fine view across the bay between Castle and Snake Islands to the mountains on the north side of the gulf. Part of a defensive wall on Snake Island and on the coast across the narrow channel can also be seen. Tomb Island is so named from an ancient sarcophagus found on it.