The Cyclades are a group of islands in the Aegean Sea with latitudes between the 36th and 38th parallel and longtitudes between the 24th and 26th meridians. The layout of the islands is in two parallel lines from Cape Sounio and Evia, which distinguish the West from the East Cyclades and together form the Cycladic Prefecture. The population of the prefecture is 112.600 according to the 2001 census and the chief town is Ermoupolis in Syros.

The name was given by the ancient geographers due to their circular layout around the holy islands of Delos (the birthplace of the gods Artemis and Apollo), whereas the other Aegean islands were known as the Sporades.

The Cycladic Islands starting from the largest are Naxos, Andros, Paros, Tinos, Milos, Kea, Amorgos, Ios, Kythnos, Mykonos, Syros, Thira aka Santorini, Serifos, Sifnos, Sikinos, Anafi, Kimolos, Antiparos, Folegandros, Makronissos, Iraklia, Gyaros, Polyegos, Keros, Rinia, Donousa, Thirasia, Schoinousa, Koufonisia and Delos as well as the complex of Antiparos and the islands of Makares on the east side of Naxos.

The six small islands between Amorgos and Naxos form the small Cyclades. These are the Koufonisia (Upper and lower Koufonisi), Iraklia, Schoinousa, Donousa and Keros.