The Cyclades , from the Greek Κυκλάδες, Kikládhes [Gr.,=circular] is the name of an island group south-east of the mainland of Greece. It is a part of the vast number of islands which constitute the Greek archipelago in the Aegean Sea. The name was originally used to indicate those islands that formed a rough circle around Delos.

The Cyclades are comprised of around 220 islands, with the major ones being Amorgos, Anafi, Ándros, Antiparos, Delos, Ios, Kéa, Kimolos, Kithnos, Mílos, Mykonos, Náxos, Páros, Pholegandros, Serifos, Sifnos, Sikinos, Síros, Tínos and Santorini (Thira). Ermoupolis, on Síros, is the chief town and administrative center of the group.

The terrain of the islands is largely mountainous, and the climate is generally dry and mild. Agricultural produce includes wine, fruit, wheat, olive oil, and tobacco.

In recent decades the Cyclade islands have become extremely popular with European and other tourists, and as a result there have been problems with erosion, pollution, and water shortages.