Peiraeus, or Piraeus (Gr. Ilecpace is), the port town of Athens, with which its history is inseparably connected. Pop. (1907), 67,982. It consists of a rocky promontory, containing three natural harbours, a large one on the north-west which is still one of the chief commercial harbours of the Levant, and two smaller ones on the east, which were used chiefly for naval purposes. Themistocles was the first to urge the Athenians to take advantage of these harbours, instead of using the sandy bay of Phaleron; and the fortification of the Peiraeus was begun in 493 B.C. Later on it was connected with Athens by the Long Walls in 460 B.C. The town of Peiraeus was laid out by the architect Hippodamus of Miletus, probably in the time of Pericles. The promontory itself consisted of two parts - the hill of Munychia, and the projection of Acte; on the opposite side of the great harbour was the outwork of Eetioneia. The most stirring episode in the history of the Peiraeus is the seizure of Munychia by Thrasybulus and the exiles from Phyle, and the consequent destruction of the "30 tyrants" in 404 B.C. The three chief arsenals of the Peiraeus were named Munychia, Zea and Cantharus, and they contained galley slips for 82, 196 and 94 slips respectively in the 4th century B.C.
See under Athens. Also Angelopoulos, Hepi IIecpauas Hai rcov Xtgivcov ai)rou (Athens, 1898).