The Cyclades archipelago (Greek: Κυκλάδες) is a Greek archipelago located in the center of the Aegean Sea between parallels 36-38 latitude and meridians 24-26 longitude. It belongs to the periphery of the South Aegean. On January 1, 2011, with the new administrative division of Greece it was divided into nine peripheral units: Andros, Ceos-Cythnos "Ceos-Cythnos (peripheral unit)"), Milos "Milos (peripheral unit)"), Mykonos "Mykonos (peripheral unit)"), Naxos "Naxos (peripheral unit)"), Paros "Paros (peripheral unit)"), Syros "Syros (peripheral unit)"), Santorini "Santorini (peripheral unit)") and Tinos "Tinos (peripheral unit)").[1]

The total population of the former prefecture is 112,615 (2001 census).

Its name derives from the Greek word κύκλος, (circle). With it, the ancient geographers made reference to the peculiar distribution of the archipelago, which seems to extend like a circle around the sacred island of Delos (homeland of the gods Apollo and Artemis), in contrast to the rest of the Aegean islands, which they called Sporades (from the Greek: Σποράδες, scattered).

The Cyclades comprise about two hundred and twenty islands, the main ones (ordered by size): Naxos "Naxos (island)"), Andros, Paros, Tinos, Milo, Ceos, Amorgos, Ios, Cythnos, Mykonos, Syros, Santorini (ancient Tera), Serifos, Sifnos, Síkinos, Antiparos, Anafi, Kimolos, Folégandros and two hundred other islands minors, of which the island of Delos must be highlighted for its historical and archaeological importance.

The geography of the islands is mountainous. The climate is dry, hot in summer and mild in winter. One of the few fertile islands is Naxos, famous for its production of potatoes, olive oil, fruits and other Mediterranean products. Olive trees, grapes, vegetables, fruits, citrus fruits and cotton are produced on the islands. The Cyclades are marble islands. There are also iron mines such as those in Serifos, magnesium, sulfur such as those in Milo, silver and zinc.[2]​ The strong and frequent sea winds sometimes cause communication problems for the ships that link the island with the rest of Greece.

The typical architecture of the towns, with whitewashed houses and alleys and brightly colored doors and windows (especially blue), are one of the greatest assets of Greek tourism, and make the Cyclades, especially Mykonos and Santorini, one of the classic tourism destinations in all of Europe.