Attica (in Greek Attiki) is a nomos (prefecture) in Greece, containing Athens.

Attica is located in what is today southern Greece, and covers about 2600 square kilometers. It contains Athens, Peiraeus, Eleusis, Megara, Laurium, and Marathon, as well as the islands of Salamis, Kythera, and Antikythera. About 3,500,000 people live in the nomos.

Attica is a peninsula jutting into the Aegean Sea. Mountains divide the peninsula into the plains of Pedia, Mesogeia, and Thriasia. To the north it is bordered by the Boeotian plain and to the west it is bordered by Corinth. The Saronic Gulf lies to the south and the island of Euboea lies off the north coast.

The process of how Attica was united by Athens is not entirely clear, but it concluded at some point in the first half of the 7th century BC when Eleusis and the surrounding plains were joined to the Athenian state, and its inhabitants became citizens. Even then, the boundaries were not fixed, as Athens struggled with Megara for control of Salamis, and with Boeotia over border towns like Oropus for centuries.

Attica later became part of (successively) the Roman and Byzantine Empires, the crusader Duchy of Athens, and at last the Ottoman Empire.\n