Attica, the most easterly region of central Greece, is bounded on the south and east by the sea, on the north by Boeotia and on the west by the ancient territory of the Megarid. With an area of 3,350 sq. km/1,295 sq. mi, it is broken up by ranges of hills, between which are four plains: the one round the city of Athens, the Thriasian plain round Eleusis to the west, the Mesóyia ("Central Plain") between Hymettos and the west coast, and the plain of Marathoàn to the northeast.
Attica has been settled by man since the Neolithic period, and it has many fortified sites dating from pre-Greek and Mycenaean times.
Tholos tombs have been found at Thorikós, Marathón and Menídi, pointing to the existence of separate principalities which lost their independence in Theseus's "synoecism". Although sanctuaries such as Eleusis with its mysteries and the temple of Poseidon on Cape Soúnion maintained their importance throughout antiquity, Athens increasingly developed into the political, cultural and economic center of Attica, helped by the proximity of the excellent natural harbor of Piraeus. Since Greece achieved its independence and Athens became its capital in 1834 a huge modern metropolis has spread far out over the central plain, and the olive-groves which once lay between Athens and Piraeus have long since disappeared. The plain of Eleusis has been disfigured by industrial installations, but the Marathón and Mesóyia plains have largely preserved their agricultural character. The coastal strips have been developed, and a whole string of seaside resorts has grown up between Athens and Soúnion. The east coast, south of Marathón, is also a popular holiday area.