also known as Tzia, is a Greek island in the Cyclades archipelago in the Aegean Sea. Kea is part of the Kea-Kythnos regional unit.
It is the island of the Cyclades complex that is closest to Attica (about 1 hour by ferry from Lavrio) and is also 20 km (12 mi) from Cape Sounio as well as 60 km (37 mi) SE of Athens. Its climate is arid, and its terrain is hilly. Kea is 19 km (12 mi) long from north to south and 9 km (6 mi) wide from west to east. The area is 129 km2 (50 sq mi) with the highest point being 560 m (1,837 ft) above sea level.
Its capital, Ioulis, is inland at a high altitude (like most ancient Cycladic settlements, for fear of pirates) and is considered quite picturesque. Other major villages of Kea are the port of Korissia and the fishing village of Vourkari.
Kea is the location of a bronze-aged settlement at the site now called Ayia Irini, which reached its height in the Late Minoan and Early Mycenaean eras (1600-1400 BCE).
In the Archaic period, the island was divided between four city-states (poleis): Ioulis, Karthaia, Poieessa and Koressos.
During the classical period, Kea (Ceos) was the home of Simonides and of his nephew Bacchylides, both ancient Greek lyric poets, of the Sophist Prodicus, and of the physician Erasistratus.
The inhabitants were known for offering sacrifices to the Dog Star, Sirius and to Zeus to bring cooling breezes while awaiting for the reappearance of Sirius in summer; if the star rose clear, it would portend good fortune; if it was misty or faint, then it foretold (or emanated) pestilence. Coins retrieved from the island from the 3rd century BC feature dogs or stars with emanating rays, highlighting Sirius' importance.