The Cyclades are a peninsula group.
The Cyclades ( [ ˈsɪklədiːz ] Κυκλάδες , [ cikˈlaðes ] ) are an island group in the Aegean Sea , southeast of mainland Greece and a former administrative prefecture of Greece . They are one of the island groups which constitute the Aegean archipelago . The largest island of the Cyclades is Naxos .