Syros (Greek: Σύρος [ˈsiros]), also known as Siros or Syra, is a Greek island in the Cyclades, in the Aegean Sea. It is located 78 nautical miles (144 km) south-east of Athens. The area of the island is 83.6 km2 (32 sq mi) and it has 21,507 inhabitants (2011 census).
The largest towns are Ermoupoli, Ano Syros, and Vari [el]. Ermoupoli is the capital of the island, the Cyclades, and the South Aegean. It has always been a significant port town, and during the 19th century it was even more significant than Piraeus. Other villages are Galissas, Foinikas, Pagos, Manna, Kini and Poseidonia.